The Haynes manual for the Audi A4 is good enough for doing most (simple) DIY-repairs. It shows in text and photo's most of the procedures and the location of all the (hidden) screws, bolts, clips, etc. Downside of the Haynes for the A4 (but that could also be the case for a lot of the other more "modern" car-manuals from Haynes) is that due to the complexity of parts and electronics several repairs are only referred to as being unsuitable for DIY-repair and the reader is referred to the Audi-specialist.