I know only a little bit about Paypal through ebay...
The only difference between the Personal and "premiere" or merchant/business account is that personal accounts cannot recieve credit card payments and business accounts can (for a small transaction fee)
ETA: link for paypal info:
http://www.paypal.com/cgi-bin/webscr...g-fees-outside
I think it's an *awesome* idea for you to start Guardians of the Diamond! (although I really liked adpiucf's "Adelphean Avengers" name
)