Have you read the articles and gear lists on the home page of this site, left-hand column?

Edit, later: There are a number of good sites about backpacking light on a budget. First, try this section of Mark Verber's site, Backpacking for Cheap which has a number of good links. Sgt. Rock's "Dirt Bagging and Deal Shopping" is a classic. Mark Henley's list on Gossamer Gear (10 lb. & $200) is another good one, although it's old enough that the cost may be $300 to $400.

The Campmor 20*F down sleeping bags (more like 30*F) recommended on those sites are, I understand, no longer available. The Kelty Cosmic Down 20 is comparable in weight, has good reviews and may be warmer since it is EN13537 rated. Do note that these inexpensive down bags are less durable and heavier than a comparable $400 bag from a high-end manufacturer, but are lighter, more compressible and more durable than a comparable synthetic fill bag. Of course a 20*F bag is far too warm for Texas summers, anyway, (might be fine for winter, though) but should work well if you decide to head for the Rockies for a trip.

Go to an outdoor store (REI if there's one anywhere within driving distance). Try out a bunch of different sleeping pads on the floor, but be sure they are insulated. You may do fine with a self-inflating pad such as the Thermarest Prolite. Or you may even be fine with their CCF pad, the Ridge Rest. If the last is comfortable, then check out one of the cheap blue foam pads at Walmart or KMart or other big box stores. Warm, but not necessarily comfortable, depending on your hip bones. As I've gotten older, I've graduated (over time) from blue foam to self-inflator to thicker self-inflater to a 2.5" insulated air pad to a custom 3 1/2" thick insulated air pad. Hopefully you are at one of the earlier stages!