If so, call any of them and ask for a poker room rate (where you play 5 hours and get big discounts). Some casinos track your hours, others do not. I just went to the Goldstrike in Tunica with the poker room rate and didn't play a minute of poker (played craps instead) and did not have any problem. But, usually if you play a few hours a day you'll be fine.
As for which casino to stay: Beau is obviously the nicest and you will probably have the hardest time getting a good deal with this one. Last time I came down, I stayed at the Isle of Capri with the poker room rate and received buy-one-get-one-free room of $79 a night. So basically, I was paying 40 bucks a night. Also, there is a cheap little hotel accross the street from the Beau (I want to say it's a Days Inn), which is cheaper than the Beau, but obviously you lose out on the nice hotel room and access to the pool area. IP is good too. Just do you homework and call some of these places. The money you save asking about comps will be worth it, particularly if you play poker.