Check the internet. I beleive RIO hotel will give you the most bang for your buck. It is in the class of one of the realy nice hotels. It is little less money because it is not located on the "strip" where ceasers, venitian, MGM, etc are located. You can easily get to the strip by shuttle. It only takes a few mitutes.

There are some things worth seeing that don't cost anything at all. The traesure Island pirate show, The dancing fountains, The Belagio gardens, The white tigers on display. One of things I always like are the blown glass flowers at the belagio front desk. AMAZING!. . How did they do that? The hoover dam is only about 30 min. drive. If I remember the tour is about 10 dollars. The visiter center is new (built 1995). . Unfortunately there is no longer an extensive tour throughout the dam. Not since 9/11. The "mini' tour is good.
Back to the strip. The elevator trip to the top of the eiffel tower is about 8 dollars. Take your own photos. The photographer there usually wants 25 dollars for a 8x10 photo of you. The venetian has a stream in it complete with gondolas and singing gondoliers. Don't be fooled the godolas have motors. Watch the gondoliers feet. He will step on a switch. That thing is "not"moving by using that stick. The clouds painted on the ceiling really do make you feel you are outside. Visit the magic shop at the venetian. The magicians are great (and free). .
I would make it a point to vistit Freemont street. I is only a ten minute drive from the strip. There are some casinos there but, the main attraction is the "Freemont Street Experience." It is an amazing light show and sound canopy along the entire street. It plays every half hour after sundown.