If you are from UK then you can register with your bank a/c otherwise no option. You can go for a VCC [virtual credit card] which you can fund with your paypal a/c but usually it is costly.
Google Adwords allows credit card and wire transfer as payment options. For wire transfer, it needs 10 business days to get funds to account of Adwords.
Yes, it really depends on the country of your location. In the United States you can buy a gift card and use it to setup an account (I'm not sure if it works in other countries). I also know advertising agencies, which specialize on adwords, that agree to pay for you with their credit card and then accept from you other payment methods.
When are these huge companies that sell and promote online going to realize that not everyone on the web has a credit card. They could probably bring in even more revenue with a new system for people with cards.
for who ever don't have a credit card you can purchase pre paid credit cards in your local area or for that matter right over the internet and you will be able to use the cards just like a credit card
If you live in the US just go down to your local Rite Aid and buy a prepaid mastercard for $20. After calling in to activate it they'll give you your credit card #, expiration date, and verification # to use right away. Problem solved.