The Burger Bar in Mandalay Place is one place I frequented. Probably the best I found near the strip. I didn't get to hunt down too many places, but their food and beer selection was good.
In Henderson, probably 32 Draft Bar at the M Resort and Spa. Fairly large draft list. I've found it quite difficult to find good beer locations in NV overall Hope this helps a little.
I know Monte Carlo had their own microbrew in-house too that was pretty good, I haven't been there in a while though so I don't know if it's still around but I would think so.
Also, I hear that Ellis Island isn't bad either...I've never been but I have a bunch of friend that have.
Ellis Island has cheap beer, It's not all that good. It's $1.50 good though. If your looking for a cheap old place then Ellis Island is for you. If your looking for a nice place to take someone too, then I would go elsewhere.
I know Monte Carlo had their own microbrew in-house too that was pretty good, I haven't been there in a while though so I don't know if it's still around but I would think so.
Monte Carlo has really good beer, not the cheapest though. The only negative to me was it's very loud, the really crank the music up.