University of St. Andrews (UK)
University of St. Andrews: James Gregory
This site, which is provided for by the University of St. Andrews, contains information on the mathematician Gregory and his accomplishments.
Rice University
Galileo Project: Gregory (Gregorie), James
This site from The Galileo Project of Rice University contains an outlined biography of James Gregory. A lot of information is contained in this site, with the topics including: dates, father, nationality, education, religion, and so on.