Seen this recently on some friend's PC and this is a tricky one to get rid of. One of the sites I've used to get assistance is bleepingcomputer.com. It is a very useful site when trying to remove some of the nasties that are out there today.
If you have run into this rogue Anti-virus piece of malware, click here for some removal instructions from bleepingcomputer. They also give screen shots and I have found it to be extremely helpful.
Here is a site where you too can get your geek on and read more about these fake AV malware types. Click here and here to read more.