I haven't taken this exam, but I have heard others recommend both Wikipedia and the Complete Idiot's Guide to American Literature. Petersons.com does have practice tests on it however.

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CLEP exams passed:
Management, Accounting, Marketing, Macroeconomics, Microeconomics

DSST exams passed:
Human Resources Management, Organizational Behavior, Statistics, Management Information Systems

Earned:
B.A. in Business Administration: Technology Management (magna cum laude) from Saint Leo University

In Progress:
M.S. in Leadership and Business Ethics from Duquesne University (24 credits completed, 3 credits in progress)