There is over 6,500 pages available to you on this web site on Ambergris Caye. If you go to the top of this page you will find a link to "lodging". I strongly suggest that you take a look at all the hotels, resorts, villas, and guesthouses listed with links to their individual web sites.
Also, you will find a "search" function near the top at the right side, and under the "reply" link. Ask for any item such as snorkeling or diving and tons of info will be at your disposal.
Victoria House is a beautiful up-scale resort about 3 miles south of the main town, San Pedro. Most diving and snorkeling is done at the barrier reef about ½ mile offshore. A boat is strongly recommended and they are readily available. This can be arranged through any hotel front desk for no extra charge. VH has a web site at: http://www.victoria-house.com/
which has a lot of the info you require.
Take the time to do some research and you will find all the info you may wish to have.
//www.ambergriscaye.com takes you to the home page of this site and all the links are listed on the left side and on the bottom of the page.
Enjoy your look at AC and have a great holiday.