Most United States Post Office materials are posted on the USPS Web site, including the three major manuals (the Domestic Mail Manual (DMM), the International Mail Manual (IMM) and the Purchasing Manual), periodicals and other publications and forms.
If what you want isn't online, the GPO Bookstore sells Post Office publications. Alternatively, call the Post Office. To locate materials for borrowing, search WorldCat.
For questions about USPS publications, call the USPS Library (202-268-2904 or -2906).
Decisions: The Postal Service posts Judicial Officer Administrative Decisions (1957-Present), Business Disagreement Decisions (2006-Present), Purchasing Protest Decisions (1996-2004) and Board of Contract Appeals Decisions (1986-Present). Board of Contract Appeals decisions are also available from 1959 to the present on Lexis (PUBCON;POSTAL) and Westlaw (FGC-PSBCA or FGC-BCA, which includes BCA decisions from all available agencies). Appeal Board decisions from 1956 to the present are included in CCH's Contract Appeals Decisions, which is available in print, on CD-ROM or through Intelliconnect.
Prices: See the Postal Rates entry for USPS mailing prices.