Method sources provide key terms, perspective, or critical lens for your research.
Best Bets:
The Johns Hopkins Guide to Literary Theory and Criticism (Ref Stacks PN81 .J554 2005)
Literary Movements for Students (Ref Stacks PN597 .L58 2001)
Dictionary of Literary Terms and Literary Theory, 4th Ed. (Ref Stacks PN41 .C83 1998)