Last time I was in Destin we stayed at the condo unit right on the old Crystal Beach pier pilings. Unfortually it was too rough to snorkle that week as the "red flag" was out because of rough waves (for Destin) and rip current. There were waves along the entire length of the pier. Too dangerous for snorkeling as having a wave knock you into a barnacle encrusted pier piling would cut you up to much.
There are only two parking places at the beach access there, FYI. To find it, look for the two Crystal Sands condo buildings. They have a green metal roof (I think) and are only 3 stories tall. The beach access is hard to see unless you slow down as it only has those two parking spaces and a "sidewalk" down to the pier pilings. I think there was a small gazebo type structure there also, but not 100% sure. While it is a public beach, they do enforce the "beach chairs are for condo guests only" rule. FYI.
Last may the "sandbar" was in pretty close, but I haven't been there after Ivan, so no telling what it looks like now.
Hope that helps some.