Did this happen and Dreamhost, or somewhere else? If it happened here, and you had him build a site on your account, there is a hidden .snapshot directly that has backups you can use.
Otherwise, unless you had a local backup, it's a matter of following the link Tor provided... and get to work rebuilding.
Once you're back up and running, you should get in the habit of keeping local backups, even though DH has the snapshots.
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