The Manda Scott 'Boudica' series of books is pretty good, although it's probably about 60% fiction it has all the timescales, battles, all the major characters involved, Boudica, prasutagas, caratacus, Decianus Catus, Paulllinus, Nero etc, it gives a bit of an insight into what these people may have been like.
Yes ok it is only a novel and should not be taken for historical fact but after reading it , it made me want to know a little bit more about the truth of it so i did a bit of research and now i'm a bit more clued up on that period of history
So i think it just go's to show that even if it's not accurate, if it sets you on the right tracks to finding out the truth in the long run then it's a good place to start