I've always used what I call the ASPIRE method. It was taught to me by an old college professor, mainly for studying historical cultures, but i have found it invaluable for creating cultures as well.
It works like this:
A - Aesthetics / Art
S - Social
P - Politics
I - Intellectual / Science
R - Religion
E - Economics
I like it. My story idea is going to involve at least two different races with different cultures, and hopefully I'll be able to use this effectively.
I've been learning a lot from the people at Writing Excuses about fictional worlds. Right now they have several free audio discussions about world building
. Hopefully someone will find these useful.
I'll definitely listen to them when I have the time.