TaxLinks http://www.taxlinks.com features revenue rulings from the IRS dating as far back as 1954. Follow the "Find a Revenue Ruling" link, select a year and click on a ruling number. Immediately after the ruling number is, in bold print, notation affecting the current status of said ruling. (i.e., Rev. Rul. 54- 1 was revoked years later by Rev. Rul. 60-184.)

The site has a search engine to help if you do not have a lookup number. The search option accepts keyword or phrase queries, but you will have to use quotation marks for phrases. And if you use more than one keyword, connect them with AND or the search engine will default to OR.

This site also links to a very decent set of tax related sites at http://www.taxsites.com. Links are divided up into a variety of categories though annotation was minimal.

AND, as you prepare for the joys of your OWN tax return time: FEDERAL tax forms and publications can be found via the IRS.

For STATE forms and publications; an excellent starting point is Louisiana State University's Government Documents Collection.