I just moved out of vegas. miss it a lot. where to stay and what to do will depends highly on your budget. I great hotel to stay at on the strip, but not be as pricey, would be planet Hollywood. ny/ny is neat, but a little pricier. and the venetian is a great place to check out, if not stay. of course that's even more expensive. check out Caesar's palace and the forum shops. Not sure how much you like to drink, but I love Fat Tuesday.
just a small bar with frozen drinks that is spread along the strip. just walking down the strip and checking out all the casino's is fun. blue man group is a great show, and on the cheaper side. And no, you can't get into sema, unless you are in the automotive industry, or know someone in the industry that can get you a pass.