I'm not going to wear a very traditional wedding dress, and I don't think that's a big surprise for most people. I'm not into ruffles or spending lots of money, and wearing it at the beach? I'd be freaking out the whole time about it getting dirty.
So I'm looking at tea-length beach dresses, and considering making it myself. These are the patterns I've seen so far that I like: McCall 4460, Butterick B4389, and Vogue 8113.
And a couple that I would consider buying: Thread Design (in green) and Jim Hjelm (also in green).