Holy that site is great and there was a book published also may have to try and pick that up some how really good reference site.
Sithtoys.com is a great site! I'm pretty sure the owner's name is Bill McBride.
"Vader - The Ultimate Guide" only skims the surface of Vader items produced, but it's still a great read.
Nice Jesse please let me know any tips you have about a Vader focus as I'm starting to do this abit myself.
The smart thing to do would be to focus on certain sub-lines, not try not to buy everything like I do. 
Howdy All!! I was pointed to this site by another forum member.
www.sithtoys.com is indeed my site, and I am also the same "Bill McBride" featured in the LFL book "Vader : The Ultimate Guide"
I love to see new people coming into the Vader collecting fold!! Trust me, there are more than enough items to go around. I think that is one of the key things that I love about having a Vader focus: there is so *much* out there to collect.
My personal "sub"-focus or rather personal priority list has always been headed by the more rare and unique items. (non-US MOC and MIB pieces, prototypes, displays, etc)
I guess my main bit of advice would be to go for quality over quantity. Anyone can pile up junk and call it a collection, it takes someone with passion and a keen eye to put together a quality collection.
Bill