I found these sites while exploring a link I posted for another thread here on the forums (http://arduino.cc/forum/index.php/topic,85335.msg706562.html#msg706562).
The first one concerns an in depth exploration of robotic arm design, simulation, control, and fabrication; the individual behind this site really impresses me with what s/he accomplished. All source code, etc are released - the only issue for me (as a "stupid American") is the fact that the site is in Spanish; however, Google Translate helps greatly here. The author covers advanced topics like IK and the Bresenham algorithm, and presents the code in FreeBasic/QBasic (if you are familiar with them), as well as 3D simulators and such employing the concepts. There are a ton of videos, and even a set of PDF files/plans for crafting a robot arm. It is a really amazing site:
The second site was actually linked off of the above site; it seems to concern the design and construction of a small desktop CNC machine, controlled by a PC parallel port. Apparently, it was built by some kids for what appears to be a science or technology fair project (?); while no step-by-step design or plan is given, there is a ton of information shown on how to achieve something similar (like most homemade CNC sites), along with some programs, schematics, and maybe some source code (?). What appears to be a good discussion on G-Code is also given. Once again, this is via Google Translate (from Spanish):
Enjoy, and I hope you find it useful, or at least interesting!