For some reason I can't add a note to the Calculators section, but anyway: here is an excellent calculator for calculating PCB trace widths - don't want to blow them up with too much current and too narrow a trace!!
http://www.circuitcalculator.com/wordpress/2006/01/31/pcb-trace-width-calculator/
http://www.circuitcalculator.com/wordpress/2006/01/31/pcb-trace-width-calculator/
