Steafan Hannigan wrote a fundamental book about the bodhrán.
This excellent tutor book helps you to get started on the bodhrán and shows you how to hold the drum and tipper the right way. It also explains how to work with the left hand to modulate the sound and gives a good oversight of the basic rhythms.
The book, (in English), has detailed illustrations and uses the arrow system to explain the different rhythms. It includes chapters about the history of the drum and about traditional Irish music in general. The accompanying CD demonstrates the various patterns..