It's the first I've heard that he wanted anything outdoorsy. Usually he wants Wii games or something for indoors. He is 12 and I'm not sure what he has or who will take him.
I would check with his father~ does he go fishing? I know that certain men prefer certain gear for fishing. Why not start easy and give him a nice fishing pole and some lures?
What type of fishing does he want to do? Fresh or salt water? From there does he have any favorite type of fish to go after? Or is he just starting out?
If he's just starting out you can just get him a simple rod and some bait. You don't want to spend a lot on it if he isn't really going to get into it.