I am leaving on a 5 week backpacking trip in a month and need to purchase a stove. My question is this..if I chose a liquid fuel stove (which I should right?) how much fuel can I expect to use and how much should I expect to carry? I have no clue how much it will use and how much to bring. Any tips would be greatly apreciated!

That depends on two things: the stove, and how you intend to use it. Boiling water and turning it off once or twice a day is a different thing from cooking a three course breakfast, lunch, and four courses at dinner.

What kind of stove you choose depends on the environment where you are going - freezing weather makes the choice pretty simple; most take white gas. For general three season use any stove will work.

lori's got it pretty much set
isobutane is pretty popular for non-freezing conditions; but if the temperature dips below 40 overnight, you should plan on using white gas, since isobutane wont vaporize properly.
if weight isn't a concern, consider propane- it's got a really low vaporization point; as a result the canisters are heavy, since the walls are so thick.

I intend to use it mainly for boiling water but also the occasional 2 or 3 course breakfast or dinner...nothing that requires the stove being on for very long though. I am still planning my menu and food and this is the first trip I have planned so this has been a bit challanging.

Im hiking in hot summer weather.....no cold or freezing conditions. It just seems that propane/butane canisters would hold less fuel and not last as long (thus having to carry more or refil more frequently) than a liquid fuel stove. I dont know..

What would you take?

also which would be easiest to refil on the trail at a grocery store, gas station, or hardware store?

I use my stove more than most: I like tea, coffee, soup, cocoa and warm water for wash-up. I use either a white gas stove or a canister stove depending on temperatures. I use about an ounce per day of fuel with either. Unless I expect really cold weather, below 20°F or so, I much prefer the convenience of the canister stove even if there is a container weight penalty. A 4oz canister weighs about 3 0z empty, an empty 8 oz container weighs a bit over 5 oz.

Others here will recommend using an alcohol stove. I use one on occasion but they are very sensitive to wind and have a much higher fiddle factor than do the canister stoves. Since they use a lot more fuel per heat than do the petro stoves, fuel can become a burden on long, unsupported trips.

If you will be five weeks without resupply, then to me, white gas would be the way to go. If you will be resupplying regularly then a canister stove would be more convenient.

there are "universal fuel" stoves that can work off "almost anything"; that'll probably be your best bet, but iirc, they're pricey

http://hubpages.com/hub/Top-Five-Backpacking-Stoves

http://backpacking-gear.suite101.com/article.cfm/backpacking_camp_stoves

http://greatescapessports.com/catalog/product_info.php/products_id/47

When it's windy I take an alcohol stove, because the canister stoves suck up the fuel like the dickens in wind. If I weren't comfortable with my alcohol stoves, I'd get a Windpro and use canisters - you can put a windscreen around the burner without putting it around the canister with a remote canister system.

Fiddle factor only comes into play when you are getting used to using the stove (or any other gear item).

What I would take depends on the length of the trip. I usually take alcohol stove(s) - they are light, I can carry two - and about 8 oz of fuel for three-four day trips.

If I were hiking the AT or similar long trail and resupply points were not likely to carry canisters, again, I'd take the alcohol stoves, which run on HEET you can get at any gas station, as well as denatured alcohol you can get at the hardware store.

If I were going abroad, I'd get something like the Whisperlite International which runs on all kinds of things including auto fuel.

If I am wanting something my non alcohol stove using fellow hikers could borrow, I take the Pocket Rocket and a large canister. I don't like canisters - you can have a partially used canister and not be certain how much fuel you have left. You can't refill them, have to carry empties to the next opportunity to dispose/recycle them, and unless you somehow rig a windscreen without enclosing the canister they are useless in the wind. If I used the canister stove more I would get one of the remote canister setups and add a windscreen. Canister stoves are very easy and mostly fuel efficient - one can make the smaller canister last for a number of days with care.

White gas is fairly straightforward, and you can easily see how much you have left and refill - I just don't like the increase in maintenance and fiddling around with all the parts, or the weight. I prefer the alcohol stoves.

People whine about the fiddle factor of alcohol stoves, but I'm not even sure what they mean - I had to laugh at someone trying to set up a Whisperlite while he was commenting on how he couldn't use an alcohol stove, there he was connecting and reconnecting all these parts and fighting with the burner legs. I was already heating water. They're slower to boil and do have a learning curve to them, but they don't sound like a jet taking off and they pack smaller and lighter... they're not for everybody because a lot of people like quick and easy, turn a knob, light it, boiling water three minutes later... but eh, whatever. I don't go out there to be in a hurry.

Any kind you choose, practice a little bit before you start, set up, how to lit up properly, power output, balance, taking down, etc...Do not hesitate to take some kind of windscreen, you can find many tips around here.

Thank you everyone for all of your input it was very much a help to me. Ill be back with more questions soon!

this
I try to 'living room (or garage) test' my gear before going out with it; that's the reason I don't use an alcohol stove- I couldn't get my particular set up to work satisfactorily; ymmv

Consider a woodburner, such as a coffee can/hobo, Bushbuddy, Bushbuddy clone(tends to be an improved hobo), or a Sierra. You'll only have the weight of the stove, and maybe some firestarter. My DIY Bushbuddy clone is around 7 oz.

Make sure fire restrictions will allow you to safely use it though.

Again, Lori pretty well nailed it. I usually carry a Snow Peak Gigapower or Optimus Crux stove, because they're fast, light, and convenient. Used with a .7L SP Trek 700 pot, or an Optimus .6L Terra Solo pot, total kitchen weight is about 8 ounces. If I'm going into cooler weather, I'll switch to a Jetboil: a canister stove that is engineered to cook in cooler temperatures and is highly efficient (4 day trip is 2 canisters with other stoves, 1 with Jetboil.) The problem is, the Jetboil weighs half a pound more than the other canisters.

Lori pretty well covered all the drawbacks to canister stoves. For a weekend, carrying a partly full canister isn't a problem (sometimes, if I've got a couple of uncertain ones around, I'll take both.) Otherwise, you'll need to be pretty certain how much is left. You can weigh a canister; most small canisters weigh about 4 ounces empty, and have 4 ounces of fuel in them. So, if the canister weighs 6 ounces, you can estimate that there are 2 ounces of fuel left. Maybe.

I also like alcohol stoves, especially a Trangia stove with a Clikstand base and windscreen, and an REI .9L TiWare unlined pot. It's efficient, reasonably quick, and very quiet. Again, weight is the reason I don't use it much: it's half a pound more than a canister stove kitchen. (You can get alcohol stove setups that are much lighter than the Trangia; I just prefer the operating characteristics of the Trangia.) Like Lori said, if resupply is problematic, I might well choose to take an alcohol stove because the fuel is available from gas stations, drug stores, and hardware stores (denatured alcohol, in the paint section.)

As far as fiddle factors, canister stoves are the simplest. Alcohol stoves are, arguably, not quite as simple, though I don't think the additional fiddling (putting the windscreen together, pouring fuel into the stove) is a burden.

What I did was get a brand new canister and light it and just let it run on medium until it runs out of fuel. I kind of lend that time to memory and when ever I light my pocket rocket or whatever I am using at the time, I just write the used time on the side of the canister after use. I still don't know how much fuel is in the container but I do have an idea of how much time I have left on the canister. Just a way I figured out how to keep track of it many many years ago and I have used this method for many years...sabre11004...

Good idea. I used to do something similar - I'd mark a line on the can (the kind where you cross the four lines to indicate five) for each meal I cooked. It sort of worked, as long as I didn't forget to record a meal.

Brunton had (maybe still does?) little stick-on fuel "gauges" for 220g cylinders. Since "shiny," "new," and "gadget" are words that make my eyes glaze over, I tried them. I found they worked about as well as similar versions for your patio grill propane tank - which is to say I wouldn't want to rely on them if the amount they indicated was near what I needed for a trip.

Actually, I've never come close to running out; if a can feels kind of light, I toss in a spare (which may be a full can, or a partial one.) But, before anyone else tries this slapdash method, they need to understand that most of my trips are2 or 3-night weekenders, with the once-a-year 5 or 6 night trip (for which I usually take two 110g or one 220g cylinder.)

I see you're in Vermont so this may not be an issue. Here any stove that doesn't have a shut-off valve is considered an open fire and is not approved for use during fire season.