The access to USA bonds of any kind available to the consumer is now called, "Treasury Direct (click here)."
A consumer of such financial instruments can set up a secure account with a log in no different than most others. I wish they were advertised more. Last I looked their interest rate beats any bank.
In TreasuryDirect, (click here) you can buy and maintain savings bonds, Treasury bills, Treasury notes, Treasury bonds, Treasury Inflation-Protected Securities (TIPS), and Floating Rate Notes in accounts with the U.S. Treasury.
Account numbers start with a letter and are in this format:*
A-123-456-789