Was just thinking that I should post a link to a little booklet. It is entitled Making Disciples of Oral Learners. It may sound boring or of no use to your setting but I believe that it can give one insight into reaching those around them (even those who are literate) with the gospel of Jesus Christ.
http://www.lausanne.org/all-documents/making-disciples-of-oral-learners-a-booklet-based-on-lausanne-occasional-paper-54.html