This may be old information but i'll pass it along.
For figuring out wattage, amps, volts and watts;http://www.diyalarmforum.com/ohms-law-calculator/
Four band resistor colors, this for LED current limiting plus voltage drops;http://www.diyalarmforum.com/4-band-resistor-calc/
I know an offensive mnemonic for memorizing resistor codes. It's awful, but it's also something that you don't forget...
and way more racist.