Yes, I'd say the number you provided is accurate, depending on the year. My class just graduated with 146, but that included PT and FT students.
There are a number of students who are interested in Entertainment Law at Boyd. We are fortunate to have a great adjunct professor who teaches Entertainment Law each year and he currently works in that field (he's also managing partner at the Las Vegas office of Greenberg Traurig). I don't personally know of anyone who represents performers/entertainers on the Strip, but all you have to do is ask around and I'm sure you can find out how that works. I do know a few attorneys who are in-house at casinos and they work with entertainers' contracts.
I do know a few students who are interested in sports law. In fact, I competed in a moot court competition at Tulane entitled the "Mardi Gras Sports Law" competition. I also know someone who previously worked for the Columbus Blue Jackets and is working for their legal folks this summer.
My advice about picking a field is to immediately begin networking with attorneys in that field. Find out who does sports law or entertainment law or who represents UNLV's athletic department. Then, ask them to lunch and find out how they got where they are. Trust me, it's pretty easy to get attorneys to talk about themselves
. Once you know how to get where you want to go, all you have to do is make it happen.