The Encyclopedia of Management Theory (link below) provides articles on theories and theorists. Use the bibliography to identify additional sources, both books and articles. Search for books and articles in OneSearch and you can also search for articles in subject appropriate library databases.
Encyclopedia of Management Theory by 
SAGE Research Methods is the ultimate methods library with more than 1000 books, reference works, journal articles, and instructional videos by world-leading academics from across the social sciences, including the largest collection of qualitative methods books available online from any scholarly publisher. The site is designed to guide users to the content they need to learn a little or a lot about their method. The Methods Map can help those less familiar with research methods to find the best technique to use in their research.
Watch a recorded demo of Sage Research Methods through the link below:
Sage Research Methods