There's also a ramp at Joe's Bayou over in Destin just around from the East Pass. Costs $10 to launch last time I was there...could be more now...but a nice place to get to the Gulf quickly.Thanks very much for the replies!
I looked again at the north end of the 331 bridge, yesterday, and noticed an old ramp, with no dock on the NE side, just north of the new one under construction.
I believe there is also a public boat launch at the end of E Hewitt, and another one on the short loop of a road to the west at the end of E Hewitt. (East Hewitt is slightly to the east of the Donut Hole (hwy98). I think the TDC has a map of the public boat ramps.