well, when you list an item for sale on ebay you chose whether to accept paypal payments, in that section you enter the pay pal email address (the email that you signed up to pay pal with).... Then when the person wins your item or buys it or whatever they go to the payment screen, select PAYPAL and then they send the payment, the payment comes through to your account and boom, youve got money in your account
After that you have two options, leave the money there and use it o buy stuff with, or transfer it to abank accoutn, this takes a little while and if its a small amount (under £50 in the UK) they do charge for it.
Need anymore info, just ask
dragon