我有在用PAYPAL支付款。PayPal目前已经是eBay的“人”了。
简单说一下吧：付款的话只要知道对方的账户信息，就是一个电子邮件地址。一般账户分个人(verified/not verified),Premier/Business Account. 我觉得personal account(verified)就比较有保障了。
大概流程personal account(sender) -> paypal account(sender) -> paypal account(receiver) ->personal account(receiver).

具体你可以去PayPal Help:
https://www.paypal.com/cgi-bin/webscr?cmd=_help-ext&source_page=_help-ext