While you cannot buy them from a government website like TreasuryDirect (which is for federal debt only), you can access these new issues through a specialized brokerage account. How to Buy Directly from the Issuer
How to buy municipal bonds: Investing in the community - Ally buy municipal bonds direct
Buying municipal bonds "direct" typically refers to purchasing them in the —directly from the issuer when they are first released—rather than from another investor on the secondary market. While you cannot buy them from a government
Unlike U.S. Treasuries, municipal securities be purchased directly from a state or city website; they must be bought through a licensed broker-dealer that is part of the underwriting syndicate. buy municipal bonds direct