Sorry to hear that you got infected. You're getting good advice from pierrefar and others here, but here's one other tip: once you get your site back up, you can doublecheck that you're not infected by using the "Fetch as Googlebot" feature in Google's free webmaster console.

When you use Fetch as Googlebot, we actually send a crawler to your site, fetch the page you request, and then show you exactly what Googlebot saw. It's an extra way to tell if you've gotten rid of the hacked junk.