I usually get my wood from Owl hardwood lumber in Lombard. They are not specifically geared toward guitar tonewoods, so you may have to search a bit for quartersawn lumber, and highly figured pieces are pretty rare, but they do carry a lot of interesting woods. They also offer cutting and planing services.
I have heard that at least one of the guys there has built guitars, so you may want to give them a call and see if someone can guide you toward good tonewoods.
I have bought mahogany, maple, bloodwood, purpleheart, zebra wood, cherry, and padauk from them, and they usually carry teak, wenge, bubinga, cocobolo, lacewood, poplar, ash, and many more. Sometimes they also have some nice veneers as well.
Good luck!