If you want to go out Hillsbourough Inlet, the best ramp is :
Alsdorf Park, at 2850 NE 14th St. Causeway, Pompano Beach. I think its $5 for parking.
If you want to use Port Everglades (probably the somewhat safer inlet for a visitor):
SE 15 Street. Ft Lauderdale. From the 17 St. Causeway take Cordova Rd. north, and SE 15 St. east. The ramps are on the south side just before the Marina. Pay for parking here also.
There are mooring bouys all up and down Broward County (somewhere around 100 of them). There are some sites listed here:
http://www.force-e.com/dive_sites/bo...ng_sites.shtml