Here is a logo designed by The Partners. They won the D&AD corporate identity category back in 2005. Its a great and simple logo with a comical element thrown in too.

The guys across at logodesignlove.com have released a free chapter from there soon to be released book. The chapters called, from pencil to PDF. It gives some great idea's for the method of your working. I would recommend it to anyone.

A logo is a graphical element e.g. ideogram, symbol, emblem, icon or a sign that, together with its logotype is recognised for immediate recognition being simple in form and conveying an intended message.

The best logos have a number of elements that make them iconic: