For those with a taste for the vintage and weird without an investment banker's pocketbooks, Dixie Guitar Traders have an awesome selection of unique stuff that is priced fairly and generally in pretty decent repair.
The guys that run the shop are very cool about things like consignment and take in just about everything brought to them, so the shop houses a menagerie ranging from derelict '80s rack-mounted processors to sitars and pedal steels. Looking to throw some new ugly into your noise setup? You could blow the dust off of oddball effects and noise implements until you get bronchitis here, and probably pick up an extra 4x12 cab for the price of your cable bill.
M.A.E. has been in business for 50 years and was at one point the source for high-end boutique guitars and amps in the area. Handmade, custom, and rare has always been the order of the day at M.A.E., and while they have shifted the focus of the store to pro-audio and back line, there are still deals here and interesting things you won't find anywhere else.
Don't forget to take a look at the wall heading toward the acoustic room or the amp pile in front of the effects display -- there are always poorly-labeled gems lurking in these areas.
Sam Ash is a national chain, yes. However, it's the people that make the difference and much like the Guitar Center in Hallandale Beach, Margate's Sam Ash is staffed by members of serious area bands and the vibe here has always made for a nice shopping experience. Need an entry level or less-than-precious instrument to tour with? You probably won't find a better deal locally.