Desdemona, I suspect the Osprey books – especially the one covering the years 886-1118 – are probably the best thing for someone who’s just beginning to look at this topic, particularly because of their excellent full-color paintings. Otherwise, the only suggestions I can add to Hypatia’s excellent list would be Warren Treadgold’s Byzantium and its Army 284-1081 , Mark Bartusis’s The Late Byzantine Army , and the several books that John Haldon has written, including The Byzantine Wars, which mostly focuses on individual battles. If you haven’t read Anna Comnena’s Alexiad , it has some descriptions of battles as well.