WorldChristian.com puts together an informative and prayer specific guide for praying for Muslim peoples across the globe. The guide is intelligent, educational and sensitive to Muslim-Christian relations. I have found it in the past to be quite helpful and motivational.
Go here for viewing the prayers guides, which can be ordered for your small group, church or friends’ group gathered just for the purpose of prayer during Ramadan.
Even as Muslim peoples fast during Ramadan, consider a special season of fasting and prayer for the 1.5 billion people. Muslim observance of Ramadan is amazingly high, much more engaged in general than we find Lent to be among Christians.