Hi Mike, sounds like you're on your way then. There are several 810 owners here so you should be able to get some good first hand advice along the way. As far as tape goes, I'd stick with the RMGI. 456 is kind of infamous for having long term problems. If you can get RMGI 468, that's what I'd stick with but having a mix of 911 and 468 shouldn't be that big of a deal. 468 is what the Tape Project tapes are recorded on and if it's good enough for Paul Stubblebine, it's good enough for us.
If you're just starting out with reel to reel, you should get yourself an operations manual (you can download this). Studer wrote some fantastic manuals and that should take you a long way to understanding how best to use your deck. To supplement the manuals, there are a couple of stickies above this forum that you should check out.
The links sticky will link you to a couple of sites that have Studer manuals and other cool Studer stuff.
The beginners guide is supposed to pick up where the manuals leave off to gain an understanding of the elements that make up a magnetic tape recorder.
Have fun!