Don't Panic!

Having your Web site disappear from public view, because it had been hacked and Google decided to black-list it, is no fun. Your business suffers, your reputation suffers and your suddenly find yourself scrambling to fix something you have no idea about.
After all, you are busy running your business, and worrying about your technology stack (Web, IT, etc), is not something you want to do.
Prevention is the best option, and for that, check my previous post "When Your Site Gets Hacked", which basically boils down to: learn all about technology, or be prepared to pay. However, if you are faced with a site that's already compromised, there is a few things that help to minimize the damage. You can read about them in this great article from the Smashing Magazine blog: Are You Prepared Against A Hack?
Read on and be prepared... or get support from someone who know what they are doing.