You'll get may different opinions on this question. All depends on what you're looking for in your vacation.
Suggest you do use the search feature to check out some of the following: Bananna Beach, Palms, Mata Rocks, Blue Tang, Sunbreeze, Banyan Bay, Victoria House. List includes moderate to higher priced places and is by no means exhaustive.
Also take a look at the "lodging" section. Can be broken down by price range.
There's a whole host of questions to consider in visiting the island including (but not limited to)
What type of vacation are you looking for? (ie lounge on the beach, super active, adventure travel, etc)
How much do you want to spend on lodging?
How close to town do you want to stay?
How willing to do most of the research yourself or should you work with a travel agent who specializes in San Pedro / Belize?
Spending a little time thinking about these questions and doing some digging / searching of the bulletin board will help you a lot.