My Diablo 3 account was hacked and my gold and items were stolen. Is there anything I can do to get them back?

When I went into my account today all my gold was gone as well as all my undamaged items. Even the items that had been for sale in the auction house were gone. I know that many people are having this issue, but I was wondering is there any way to get the stolen gold and items back?

As per http://us.battle.net/support/en/article/compromised-diablo-iii-account:

Compromise Restorations in Diablo III will be based on automatically saved restoration points. Restorations will be provided by rolling the entire account back to a restoration point.

In other word, if you contact Blizzard about it, they are going to restore your account to the latest backup they have.