Stop worrying about attachments and gear and new guns and whatnot. Find yourself some good (full-seal) eye protection, a pair of good boots, and go play! Don't be shy around other airsoft players who are decked out in camo and plate carriers. Talk to them and ask about their gear. The one thing you'll soon notice about airsoft players is that we love to talk about our gear. Ask them questions, and learn all you can from them.
After you play one game and talk to a few other players, you'll get a better sense of what you want, and what your next steps are.