You have to check, lots of Vegas courses close in Sept and October for overseeding. I'm going in Sept also, and a lot are closed.
Off the top of my head ,nice Vegas area courses I've played are The Badlands, Primm Valley, Coyote Springs (tough). Check Golfnow, they have some deals, as does Tee OffTimes.com Another nice, cheap course was Boulder Creek, not the Boulder City course, we played it for $34 and it had the best greens we played all week. It's on Golfnow or Teeofftimes.com