It looks like Luciana signed quite a few pictures for autographworldllc, they already have the third batch of autographs open for bidding on eBay. You can find them here and here.

If you are looking for something smaller, you might also be interested in the signed trading cards that regularly pop up on eBay, for example this one. These cards are no prints of her autograph, Lucci confirmed to me earlier this year that she indeed signed all of them personally.

Related links: eBay thread and discussion about the autograph card on the fanboard.