The best manual is by Bentley, as in Bentleypublishers.com! That being said, for the casual user maintaining their own car, the Chilton Passat/A4 manual is handy to have. This is because it has lots of photographs, and step-by-step pictorials that Bentley assumes the mechanic doesn't need.

As far as I can tell, the hazard switch/turn signal relay is one unit. I saw a price of $59, however this thing connects to the turn signal switch on the steering column, which could also be the problem. Probably the quickest way to find out is to substitute a known good unit, and see if your signals work.