The most recent edition of the Ordained Servant (produced by the OPC) is on the topic of Encountering Islam. From the editor:
Since September 11, 2001, Americans have discovered that we can no longer ignore Islam as a political force or as a religion. The confusion of those two realms is inherent in Islam, and, sadly, is found with some Christians as well. For Christians, the danger in the confusion is to consider Muslims our enemies, when we should be seeking their salvation. Some Muslims are indeed our political enemies whom we have a duty to defend ourselves against as citizens; but, as the church, all Muslims should be the objects of our evangelistic concern. Only when we carefully distinguish between the spiritual and temporal kingdoms is such concern really possible. As enemies of God, Muslims must be told of the reconciling love of God in Jesus Christ.
Here are the articles in this edition:
Paul in Mecca, by Gregory E. Reynolds.
How Should the Reformed Church Respond to Islam?, by Bryan D. Estelle.
City On A Hill: Caesar’s or God’s?, by Richard M. Gamble.
The Truth about Islam, by Gregory E. Reynolds.
The Crisis of Islam, by Donald M. Poundstone.