The U.S. Treasury Department recently released a memo (PDF) that sheds some light on the issue:
http://www.taxfoundation.org/blog/show/341.html
Amazon.com: America: Who Really Pays the Taxes? (9780671871574):
Price:  $24.95     10 Reviews
America: Who Really Pays the Taxes? (Paperback) ... 3.0 out of 5 stars America: Who Really Pays the Taxes; I have found this book rather boring. Taxes aren't nearly as thrilling as a Tom Clancy novel. But I have learned quite a bit from this reading.
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Yes, income in America is skewed toward the rich. But taxes are skewed far, far more. The top 5 percent pay well over half the income taxes. STEPHEN MOORE has the numbers. ... 2. What income group pays the most federal income taxes today? ... Who Pays How Much in Taxes...
www.american.com/archive/2007/november-december-magazin... www.american.com/archive/2007/november-december-magazine-contents/guess-who-really-pays-the-taxes
The top 5% of taxpayers pay more than half of all personal income taxes. The top 1% earned more than $269,496 in taxable income and paid 34.8% of all personal income taxes - average rate 27.1%. The top 5% earned more than $114,729 in taxabl...
http://www.normanjohnsoncpa.com/fft/whoreallypays.htm
The initial impact of state and local taxes falls mainly on business, which pays almost 60 percent of the taxes collected in Texas. Property taxes constitute nearly half the taxes initially paid by business, and the sales tax accounts for a...
http://www.internationalbudget.org/cdrom/papers/tax/Tex...
WHO REALLY IS THE MAJORITY WHEN IT COMES TO MONEY, RED STATERS OR BLUE STATERS, AND HOW MUCH MONEY DOES THE NATION REALLY HAVE TO WORK WITH? ... In other words, the gross intake from every source of revenue by our federal government each year, including taxes on liquor, gas, and sales taxes, adds up to just slightly under...
www.moderateindependent.com/v2i22taxes.htm www.moderateindependent.com/v2i22taxes.htm
I really try to avoid anything that smacks of politics, but I can't help setting the story straight on a popular American myth — repeated with increasing frequency in this election year — that "The Rich" (whoever "they" are) don't pay their fair share of taxes.
www.foxnews.com/story/0,2933,121811,00.html
AskQuestions.org an online news site that addresses issues raised by public demand released a report today on Who Really Pays Taxes in America?
www.commondreams.org/views04/0416-08.htm
The big picture lies in the sharp turnaround since 1950 in who pays the taxes. In that year the tax system was gearedf toward broadening membership in the middle-class, ... America: Who Really Pays the Taxes, April 6 2000 ... America: Who Really Pays the Taxes? by Donald L. Barlett (Paperback - Mar 23 1994)
www.amazon.ca/America-Who-Really-Pays-Taxes/dp/customer... www.amazon.ca/America-Who-Really-Pays-Taxes/dp/customer-reviews/0671871579
Answering “Who Really Pays Taxes?” required the AskQuestions.org team to assemble a dozen practical suggestions from a range of experts about increasing the fairness of the tax system while also making it more effective at stimulating the economy.
www.thenews.com.pk/daily_detail.asp?id=167474