I wanted live music for my wife's birthday party last year, and did fine just finding someone on the beach. We found a great three piece mento band on the beach, and they accepted my 1st offer of "Hey, can you guys stop by on Friday night and play for a half hour for Fifty U.S.?" We ended up tipping pretty well on top of that, but they were just perfect for what we were looking for. You would probably be fine doing the same thing, just hang out on the beach, see a musician or band you like, and make an offer. Shouldn't be too expensive.