The following links will take you to various parts of the US Treasury. While they call sales "auctions" these are not the sort of "auctioneered" sale most of us think of.
Treasury Sales & Auction
Treasury Direct - investment options
Typical "Auction" Record/annoncement
Treasury Bulletin Index
Buying Treasury Securities
Rules and Regulations
Federal Registry Rules on Bonds, Notes, Bills
Types of Savings Bonds
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