I also agree. A guidebook can be quite useful for planning. I would never take one on a trip, though I have copied or scanned a few notes on occasion. Do remember, though, that the trips listed in the guidebooks will have more people on them.

The other useful planning tool is the larger scale Forest Service maps of wilderness areas. For example, I found the USFS Bridger Wilderness map a far better planning tool for the west side of Wyoming's Wind River range than the Earthwalk Press maps. The latter don't have nearly as much detail and are also heavy and bulky. However, I've stopped taking the whole map anyway and instead scan and print out the portions I'll need, and only if I need a supplement to topographic maps. I've been known to cut maps up, too.

I have planned plenty of trips using only USFS and topographic maps. I wouldn't do this until you've had more experience in that particular region, though.