Scooby Mystery Day: Unmarked Mail

So I have a case for Scooby Doo and his gang of teenage detectives, however you guys will have to help me since Scooby was busy eating Scooby snacks when I called the Mystery Van (they are with the times, and have a cell phone of course).

I received an envelope with a return address that I have never seen before, and no name. It was also just addressed to my last name, no first name…. I am hoping someone will step forward and admit to making my day better here.
These are the two cards this person sent me, both of which I love and needed.
Albert Pujols 2005 Donruss Elite

The reason I want to know who sent them is so I can thank them and perhaps send something in return. I love getting mail from bloggers, and traders but I would also like to be able to thank people as well. This was a very nice gesture on two hard to come by Pujols cards.
P.S. If you are waiting for a card/trade from me I promise to mail them tomorrow. My brain has been out of blog mode lately because I had a test today. Now I can relax a wee bit and work on mail and posting some stuff.

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