When purchasing items from another country, can I just ask people to consider first of all how they are going to make payment...
International bank transfers still remain extremely expensive (here in the UK, my bank, Santander charge £25 to send money to a bank outside of the UK). That said, some people have got around this by paying direct into my bank account using a local branch (although Santander say the fee should still apply as Santander UK is not the same as Santander Spain).
Some countries have their own intra-bank transfer systems which can be made at a low rate, but generally these are limited to only a few banks who have to be signed up to the scheme, and may even be limited to a specific country.
Another option is Western Union, but sending cash by Western Union can be fraught with risk, as there is no easy way of proving who received the payment. Western Union online do now offer a system for transferring direct to someone else's bank account - and this is fairly low cost (4.90 GBP).
By far the easiest way has to be PayPal (although I know a lot of people seem to have something against PayPal) - you do not even need a PayPal account to use this to send a payment - if the seller accepts PayPal, you can click on the link and simply enter your debit or credit card details direct into the secure system offered by PayPal.