There's all kinds of wilderness specific maps out there as well as Forest Service maps that will have the wilderness boundaries.
I have both - go to the nearest FS office and get their maps and go to REI or somewhere like that for the wilderness-specific maps. When you start narrowing your area, you can get some Green Trails maps to see specific access trails, etc.
Of course, I like my maps. I also have the Nation Geographic Topo software which has a free add on pack with the GMU boundaries (2008, but they mostly haven't changed.) If you figure out what GMUs the wilderness areas are in, you can find it on your digital map.