A good sea kayack?

[HighTide]

I've done some canoeing, of course, I've had fun in plenty of rowboats too. Did my share of rafting too- and a little bit of kayaking on rivers and large streams. However, last summer and this fall was the first time I actually used a sea kayak- in the sea. I think I might want to buy one, strap it to my car, go for a drive, and take it out. However, I don't know much about brands, and what to look for while shopping around. Any suggestions? I'd really appreciate it! My friends are all motor boaters and sailors (I love both!) but they can't really help me on this.