Welcome aboard! You'll find plenty of teams here to choose from. The USMC team mentioned would seem to be an obvious choice but I'm sure you'd be welcome on any of the teams. Really is up to you and what you might be looking for. Some are small, others large, some international, others country specific and many with special interests. The search function on the team page will let you search for a team given your interests. You can browse the team threads here too. Of course, you'd obviously be quite welcome on mine too