Some Model Acts are published in West's Uniform Laws Annotated, including the Model State Administrative Procedure Acts of 1961 and 1981.
The American Bar Association publishes a number of Model Acts including the Model Business Corporation Act and the Model Nonprofit Corporation Act. The MBCA is discussed further in the "Corporate Law" entry. The RMNCA is discussed in the "Nonprofit Organizations" entry.
The National Conference of Commissioners on Uniform State Laws posts the full text and related information for some of their model Acts. NCCUSL Acts are generally referred to as "Uniform Laws" and are discussed further in the Uniform Laws entry.