Hello Chris, and welcome to PC.
We're always happy to welcome new members on board, especially those interested in trading and battling. Cirno has already showed you the Battle Center and Trade Corner, which should have you covered. We also have a Pokemon Showdown server where you can battle other PC members, and you can chat there too! As for Pokemon games, I've played Ruby, Pearl, Platinum, SoulSilver, Black and Black 2. And I still play Pokemon games despite recently hitting my 20's. I'm enjoying Black 2 a lot right now, have to go through Route 7 next, which I'm really not a fan of (that darn grass!).
And wow, you've completed the Pokedex on a lot of games? Not even I could ever do that. I know how hard it is getting hands on Shinies, especially given I haven't seen any in Black 2 yet, but I have in my other games. We have an Eevee and Eeveelutions Club you might want to join, since you apparently like Jolteon. I like the Oshawott line better though, cos I am a true Oshawotter myself.
I'm Hikari, and feel free to shout me a VM if you need anything!