Recomendded Links:
This site contains lots of free electronic circuits (schematics) & do-it-yourself (DIY) circuit diagrams for hobbyists, students, professionals etc. covering a wide range of categories in electronics like audio, computer hardware,radio,robotics etc.
The site includes over 100 circuit diagrams.
Control of Stepping Motors, a tutorial
This tutorial covers the basic principles of stepping motors and stepping motor control systems, including both the physics of steppers, the electronics of the basic control systems, and software architectures appropriate for motor control.Written by Douglas W. Jones, associate Professor in Iowa University.
Resistor Color Code Calculator
Nice - A calculator to find the value of a resistor by the color code.