Jeremy,

Welcome to the forum.

That initial 100mm x 100mm project sounds fairly straightforward, should get you running in no time :D That work area is fine for many PCBs and if you want to go larger you'll just have to be creative about registration methods/jigs.

Screws and rails on Ebay - you're probably refering to MD (we've all bought from there with varying experiences) - but have a look at Gary's site http://www.slidesandballscrews.com/ also Lee, the site owner, may be able to help.

Don't forget to post your build log!

Irving...