Trouble with bad plugin – HELP!

Hi!
I wasn’t sure where the best place to post this was, so I apologize if I picked the wrong location.

I have had a problem with my server getting hacked. My host service and I have narrowed it down to that it must be coming from one of my plugins. I have updated the WP installation and the them and all of the plugins.

I have scoured over all of my plugins and I just can’t figure out where this hack is coming from. Is there some instruction that someone can give me for figuring out which plugin might be corrupted without trashing my whole site and all of my plugins?

Any help would be greatly appreciated! I have had to major hack attempts in as many days and my nerves are shot :p