Tax Notes has published an article discussing new IRS Publication 551, which explains the basis value to be assigned to individual assets. IRS Publication 551 "explains to taxpayers how to determine and use basis to calculate depreciation, amortization, depletion, and casualty losses, and to find gain or loss on sales or dispositions of property."
See "IRS Releases Publication on Basis of Assets" 2011 Tax Notes 146-37 (July 29, 2011)
Posted by Jason Tyler Young, Associate Editor, Wealth Strategies Journal
The link to Pub 551 is as follows: http://www.irs.gov/pub/irs-pdf/p551.pdf