Welcome to the forum. I can't speak from experience, as I have never had a Thunderbird, but I have found this site to be helpful when it comes to deciding what car to buy. Just be sure to have some extra money set aside as most older or high mileage cars will surprise you with something. Welcome aboard!
Hey, welcome! The 97 is a good year but keep an eye on your head gaskets. Not sure about that year, but the earlier 3.8's were famous for spitting out head gaskets. My Mom's husband has a 94 3.8 with over 400,000 kms on it, but it's been through two sets of head gaskets. Other than that, I've heard no other complaints about the T-birds
I have a 94 4.6L LX with about 200k Miles on it. So far everything been smooth minus the time I had to replace the injectors. I'm not very familar with the '97 model but ifs your only paying $500 for it I would take it for a few test drives... Its not a lot of money if something goes wrong but the fact is.. the guys not asking a lot for it which could mean there's something bad that's hidden that you might not know until a long trip.