Rockport has lots of places to fish, if your planning on camping I'd recommend Goose Island State Park, it offers good wade fishing, a pier to fish from, a boat ramp to launch if you decide to take your boat, bait shack etc..
Get yourself a Top Spot map, take the boat with you, find mesquite bay, plenty of good spots to fish there and easy to find if you've never been there.
Be sure to read that map though, lots of shallow water and shell reefs around the area there.
To find out if fish are biting go to
www.fishrockport.com and click on "Guides and Reports".
Good luck!