Questions from a newbie

Hey, I'm 23, in Atlanta, and trying to get into open water swimming, because it seems like fun, it's something new, and because keeping track of how many laps you've swum is hard when you're tired. :P Through middleschool, I was very active in swimming, and did tons of competitions in my region. In highschool I switched to running XC, which I was not as good at, but which had more hot chicks at my school. In college I dropped team sports completely so that I could focus on drinking beer and eating pizza. Now I'm recovering from the weight I gained during undergrad, and swimming was a natural choice since running continues to give me shin problems. In the pool I've been able to swim as much as 3 miles with relative ease (I did 210 lengths of a 25Y pool yesterday, and I feel great today). Obviously, it's the dead of winter right now, so there's probably not a lot going on in the realm of open water swimming. Anyway..... 1. If I want to prepare for a 5K open water swim how far should I swim in a pool? Are the two even comparable? 2. Do I need a wetsuit? 3. What groups in the Atlanta area do open water swimming? And how soon in the year will people start swimming outside? 4. Just how inadvisable is it for an OW newbie to swim alone outdoors? 5. Do people always swim freestyle in OW races? My ***-stroke is a lot easier for me (I do about half and half when I'm swimming laps at the pool), and almost as fast. Will people look at me funny (or will I be DQ'd) if I switch strokes during an OW race? 6. I'm a little bit intimidated by the notion of going out with some OW group, given that I'm probably not nearly as fast as them and I don't want to hold them up. Should I be training on my own to get faster before I try to join a group, or should I just dive in and see what happens? I guess that's it for now. Thanks for any tips/advice/answers you've got for someone looking to get started with open water swimming!