I was infected when the site was down. The virus puts a hosts file on your machine which pre-empts a dns lookup.
search for a file called "hosts" on your machine and either delete the whole file or just the lines that refer to google. On windows xp the hosts file should only be in the c:\windows\system32\drivers\etc\hosts, but IIRC there are a couple of other places you can put it & windows will find it. This is usually where the virus puts the hosts file so you probably should be able to delete it safely.