Free books in the library.
You can obtain a lot of tutorials online, including short videos.
http://www.mvps.org/dmcritchie/excel/excel.htm#tutorials
then perhaps purchase a reference book after you've gone through
the tutorials. You should have a pretty good idea of what you want
by then. Actually you can get everything you want from web sites
if you weed out the advertising sites that regurgitate
newsgroup postings such as the site you are posting from.
