I believe you can bookmark threads, I think you go to the thread you want to subscribe to, go to the top of the first post (along the black bar), go to "Thread Tools" and then click "Subscribe to this thread".

Anyway, welcome to the community! I hope you enjoy it here c:

I actually went straight to Judo, but I later found that aikido and ABD were more fun. Also, I'm not sure about official merchandise D: