To search broadly in the CAT or other library catalogs use the Library of Congress Subject Heading, 
     Missions, American

Organizational Records
Search for organizations as authors to find records.  

•     American Board of Commissioners for Foreign Missions 
•     American Missionary Association
•     Presbyterian Church in the United States

Missionary Magazines
   Use the subject heading "missions periodicals" and limit by publication date to find magazines published before 1900.  A few examples;   

• Baptist Missionary Magazine
• Missionary Herald
• Woman's Missionary Friend