Depends on the rose, to a large extent. Climbers and HT and bush roses usually topped a bit in Autumn, then pruned properly late Feb or early March (depending on the weather), cutting back to an outward facing bud, removing dead wood and any weak, damaged stems or stems which cross over one another. How much you cut off also depends on the rose and how vigorous it is - some vigorous varieties shouldn't be hard cut back because they just get even bigger, so these need medium pruning. Ramblers should be done in September. You might be better off getting yourself a copy of D. G. Hessayon's The Rose Expert - good guidance in there and it's not an expensive book.

Yes, the 'expert' books are great. Or for more depth try RHS Training and Pruning from Dorling Kindersley.