I used to sail out of Assateague NP, too! It's been a long time, though. There are some launches up above Fenwick into the river(?). I think mostly kayakers and sup people use them now. You can also launch into the bay from the park on route 90, but you'll need beach wheels- there's no ramp there any more. I last sailed there about 3 years ago on my 14. If you're up for a bit of a drive, head down to Hatteras, NC! Plenty of beach and launch sites both ocean and sound side. Only problem is, thanks to the ecoterrorists, NPS requires a permit and fee for beach driving- even on the siound side.