You're not gonna get the best on the strip for cheap, but you can find decent stuff.
Treasure Island is about $120, New York New York is $100, The Monte Carlo is $95, the Excalibur is $55, Circus Circus is about $45.
New York New York is probably the best out of those and sometimes they give a $10 airline discount, but TI is nice too. If you plan on going Thurs - Sunday plan on paying about twice that.
Excalibur is probably the best deal for the really cheap ones on the strip, but you get what you pay for, so expect a lot of children, and less than desirable guests. If you don't plan on staying in your room much, then it shouldn't be a problem.