My evaluation will be divided into three parts. First we must study Exodus as a whole in order to discover its main concern. Then we will examine the plagues in order to describe their purpose. By relating these two parts together we will be able to evaluate the significance of the plagues.
A classic theological commentary by father of canonical criticism
Major study reissued in 2010.
A significant evangelical commentary.
Major commentary by leading evangelical scholar
Much of this important book by Tremper Longman III is accessible through Google books linked at the bottom of this post.