the following quite recently for beginners:

pubs.logicalexpressions.com/.../LPMFrame.asp
h&AUTH=33

Or of course there's her own site mousetrax.com.

Another couple of sites which I've found immensely helpful are:

http://www.cpearson.com/excel/topic.htm

http://www.mvps.org/dmcritchie/excel/excel.htm

Should get you started.