http://gf.state.wy.us/
Most of the draws are done, what you're likely going to want to look for are the "Leftover Draws" (deer, antelope, and elk) which I believe opens July 10 and closes July 20.
The guys behind me during spring turkey season were buying their nonresident spring turkey licenses over-the-counter, I think those are also available OTC in the fall. I don't think you can buy a NR big-game tag OTC.
Would definitely read the regulations - they should be available online, too. Might not hurt to find some USGS quads of the area(s) you think you may want to hunt.