TRAC IRS http://trac.syr.edu/tracirs/
Syracuse University-based research project (Transactional Records Access Clearinghouse), that collects and reports on IRS enforcement policies and practices, and publishes IRS data of interest to all taxpayers.
The Tax Prophet! http://www.taxprophet.com/
Original content on U. S. income taxation, plus professional tax articles, newsletters, hot topics discussions and colorful features.
TaxCreditResouces.org http://www.taxcreditresources.org/
Information about federal and state tax credits for low-to-moderate income families, with online eligibility review. Sponsored by Community Resources Information, Inc.