Hi Cory,
I'm new to deckbox as well - but I'm "old school" MTG, who recently jumped back in because my son got into it, so I have a good number of the newer sets, but am always looking to expand. To be honest, while I'm not going to ignore the value of cards, my son and I actually play a bit and like to build decks, so your offer is intriguing to me.
Little history - I started in Summer 93', so I just missed Alpha/Beta, which is definitely a bummer. However, I have an almost complete edition of Revised, along with most of The Dark, Ice Age, 4th edition, and basically everything that came out through 1997 (with some random elements up until around 99-00).
Anyway, I haven't listed my "old" cards yet - I was busy sifting through the piles of new cards.
If you have any interest, drop me a line and maybe we can work something out. I'll eventually upload all my old stuff. All of the cards are in very good shape, with me actually never having played most of the mirage+
Of course as a new trader, I have no idea how the system works or what kind of proof we're working with, but I'm willing to give it all a shot.