Hey mate,
with regard to buying kit, one thing you should really endeavour to do is try before you make any decisions. Go down to your local site (where abouts are you based?) and speak to the people down there about what guns they shoot, what masks they were, ask to have a go, most will be only too happy to help you out.
also with regard to starting out, you could do a lot worse than to buy your gear second hand (from a reliable source), either from people at your local site, or from the classified section on these forums. The second hand car market looks healthy compared to that of paintball gear...
Any questions, feel free to ask, most people here are more than happy to help you out