For various reasons we are switching from doing unit 4B with our A2 Geographers to Unit 4A. Going from Issues Evaluation to the fieldwork / skills paper.
This book is the best book on fieldwork that I have seen. It explains every skill in the AQA AS and A2 syllabus in really easy to follow student friendly language.
I am also planning on using it with my IB Geographers for their Internall Asssessment, there will also be pages that are useful for GCSE Geography.
Well worth a read!