If it's private and you hesitate, just don't do it. If it's for your work and your boss or IT dept wants it for some reason, ask them to provide an introductory course on this new program.

All of the Office Help is on the web, and it should be accessible from inside Office if the site isn't blocked. If it's at work, let the IT guy solve this.

http://office.microsoft.com/en-us/word/HA100625841033.aspx is the particular page you are looking for (it was the first google hit when I searched for "Locations of Word 2003 commands in Word 2007", with quotes of course). It was so easy to find, in fact, that I wonder why you couldn't. Don't you know how to use google?

And http://office.microsoft.com/en-us/word/FX100649251033.aspx?CTT=96&Origin=CL100636481033 is the top-page for Word 2007 help.