If you use AW you can take a credit voucher from the client, all he needs is an email address for you. If you withdraw the credits you do lose 30% as an admin fee to the site, so if you had 75 credits you would get ?50. Or you can use the credits to promote your page, display your number, buy items from AWs market place etc
I've also had clients top up my work mobile phone and send me the payment reference number or buy me Amazon vouchers.
There are also cards like 360 mentioned on the second page of http://www.saafe.info/main/index.php?topic=1547.15 this topic, I think Paris would be able to give your more info on them.