Summary

Here I uploaded some files if someone wants to make one.

It works great, I just have to make some adjustments to make it work better.

I used:

2 Stepper motors 28byj-48 (With the ULN2003 drivers).
1 Arduino uno.
1 Servo.
3D printed pieces.

Everything was printed out with 0.27mm layer height, 10% infill

I also uploaded some images of the plotted image.

A video how it's working now.
http://youtu.be/CjxjyHekW7s

If you have any question just send me a message.

UPDATE 05/23/2014:
I added some weight on the pen holder to keep it steady (just putting inside two AAA batteries.
Also I uploaded some pictures of the image printed today.

UPDATE 06/04/2014:
Here is the link to download the necessary files to make it work.
https://github.com/ffleurey/Makelangelo

Thanks to #drbogger who made me realize that I didn't upload the files or tell you guys where I got the files from.

Sorry for the delay.