[Scottish] Fraudulent Internet use of my debit card

[John Gordon Ollason]

I suppose it's inevitable, but my bank statement came back this month and  
somebody had spent £3000 of my money purchasing stuff on my debit card  
using the Internet.

In the last 6 months the only other purchase I made on the Internet was to  
Amazon UK.

What is the likelihood that I have picked up malicious javascript or  
whatever?
If I have picked up something nasty how do I go about finding and getting  
rid of it?

I browse using Opera, Firefox, Konqueror, and rarely with Amaya.
I am running Fedora 4.

Any advice will be welcomed.

Thanks,

John O.