If you live outside the USA and are promoting Amazon.co, Amazon will only pay you by cheque or gift certificate. There is a way, if you are based in the UK, to pay in these cheques without incurring excessive bank fees.
In the UK, when you pay in a dollar cheque to a sterling account you end up with a lot of fees – usually a one off fee plus an unfavourable exchange rate.
What you can do (if you live in the UK) is pay the cheques into a US dollar account that that can be opened with Citibank. This is free, can be done by post and doesn’t have any fees. You pay in your cheques via post. Check out this link and see which account is right for you:
You can also do this for Euro accounts (e.g. if you are promoting amazon.de and you are in the UK) but I haven’t done this personally.
Once you have paid into your citibank account, you can use it to pay for things in dollars or link it to a Paypal account and transfer money that way (you still get fees via Paypal, but will be less).