Principles of Microeconomics by Greg Mankiw is a good choice if you're looking for a textbook.

Principles of Microeconomics: 9780324319163: Economics Books @ Amazon.com

If you're looking for something much shorter (say, study-guide length), try Microeconomics as a Second Language by Martha Olney.

Microeconomics as a Second Language: 9780470433737: Economics Books @ Amazon.com

If you want something that has a more Freakonomics style to it, try Tim Harford's The Undercover Economist.

The Undercover Economist: Tim Harford: 9780345494016: Amazon.com: Books