If you plan on using spinning tackle and going on your own, then this site will help you select tackle -
http://destinationsbelize.com/gear.htm I think you'll find that most light to med freshwater gear will work. These are a few other sites where you can get more info on tackle and species.
http://www.angleradventures.com/blzwtb.html http://www.belizeflatsfishing.com http://www.prflyfishing.com/Belize/belizefishinggear.htm I've posted this link before, but here it is again.
http://globalflyfisher.com/reports/belize2002/index.php This article is mostly based off of guided trips, but also contains a review of many locations to fish on your own.
I have hired a guide myself for Tarpon, Bonefish and Permit on fly, but I'll also be fishing on my own as well. The issue with fishing from docks and piers has been covered on this board before. Most of those structures near town have restrictions on fishing(for safety reasons - swimmers). However, it appears that many of those north and south of town are OK to fish from. It wouldn't hurt to ask a local nearby. The reef is quite far from shore, so I don't think you'll be wading around out there and there's no reef close to shore(except artificial reefs created by resorts). Even if you could wade the reef, you shouldn't, since it's a reef, and you'll only wind up causing damage.
You'll have to consult others for limits and size. I intend on returning everything I catch, so I never bothered checking.