Ryan,
Welcome--and I echo all the others. Join as a full member...for all the reasons noted.
There is most definitely NOT one place to consider "the best" to get parts from.
I was where you were in 1999. Car had been sitting since 1985. I knew nothing much about the model, and little about the parts suppliers. So I joined the MBCA (far more active then than now); made friends (invaluable) with fellow members, found the old Yahoo! forums which in short order became this forum and the club.
I have bought parts from darn near everyone who is in our vendor list, and went searching for a bunch at that time who today are no longer in existence. At that time definitely the most useful parts suppliers for me were Caliber Motors in Anaheim CA (which became Mercedes-Benz of Anaheim Hills); there was a guy there named Tom Hanson who later went to the Classic Center when they started up. He was a wealth of help. (Tom has since retired from the Classic Center, and the Classic Center moved from Irvine to Long Beach) In addition, I cannot say enough nice things about Mike Ochoa at Miller's Mercedes. Mr. Miller retired, sold the company to a husband/wife team, are now headquartered in Phoenix, but last I heard Mike Ochoa was still there.
What separated these two vendors from the rest (some at the time, who are now gone, were so arrogant as to not return phone calls or emails) is that they were exceedingly helpful at that time to help a newbie who didn't know what he was buying. So when I said I wanted to do X, and to do that I think I need A, B and C, they would say you also need D, E, F, and while you are at it, you may as well choose to do Y, and for that you'll need G, H, and I. In other words, they were visualizing what my goal was and ensuring I had all the parts I needed and also replaced or restored other parts "in the way" of getting to what I needed. Now that's a great vendor.
But if you look at our vendor list we have a LOT of fine vendors that help us all to keep these cars running...
