This site has a number of 'how to' pages for refinishing, repairing, etc, along with identification of woods (couldn't connect with that one today).
http://colonialantiquemall.com/asklee.htm
This site identifies American furniture styles.
http://www.artworkers.com/furniture_style.html
I haven't looked at either site much, but at a glance they looked informative.
BTW, the greatest search engine in the world IMO is 'alltheweb'.
Carol