Try this site.
You won't believe what an incredible hassle it is to find all the parts. A major problem when I used Dave Rigotti's plans was when I bought the lead screws from the company he recommends. All you get is a section of lead-screw with threads up to the very end. You can't properly attach a coupling to the ends because of this, so you have to find a machine shop to turn down the ends to a rounded cross-section. What a major f--king hassle.
I called the company, and they told me it would cost me a few hundred dollars to even chuck-up the lead screws that they had already sent me. Or, I could have a local shop do the same. How about I just flush my money down the toilet?
Fortunately, there are sellers on Ebay now that sell lead screws for hobbyists. They are ready for use without any additional lathe work.
Then the "door stop" material isn't available from the retards at "Home Depot" (Home Cheapo). So, it would have been nice had he used more standard dimensions that the big-box stores offer. Cutting down your over-sized material just doesn't leave as-nice of a finish as the factory finish. (OK, this can be overcome, but it's just so much easier to buy material that only needs one-dimension cut)