well, first off, this is a better question to go in history (or a PM to be honest...)
but If its Byzantium you want...well, I havent rerad any specialist Books on it (in fact most of the info m I know on 'em comes from me researching on the net about specific parts of the history to back up my arguments in threads, it just happens that my educated guesses happen to be right most of the time
)
but here are some good sites (which in turn have book lists)-
http://www.wsu.edu:8080/~dee/MA/BYZ.HTM
http://byzantium.seashell.net.nz/index.php
here are some books from a few milatary sites I frequent-
A Short History of Byzantium by John Julius Norwich
Byzantium: The Early Centuries by John Julius Norwich
Byzantium: The Apogee by John Julius Norwich
Byzantium: The Decline and Fall by John Julius Norwich
Byzantine's Balkan Frontier: A Political Study of the Northern Balkans 900-1204 AD, by Paul Stevenson
The Byzantine Wars, by John F. Haldon
Byzantine Court Culture from 829 to 1204 AD by Henry Maguire, ed.
The Days of the Warlords, by Paul A. Blaum (focus on Basil II's defense of his throne against the claims of Bardas Sclerus and Bardas Phocas).
The Making of Byzantium, 600-1025, by Mark Whittow
Warfare, State And Society In The Byzantine World 565-1204 (Warfare and History Series) by John F. Haldon,
Late Antiquity: A Guide to the Postclassical World, by G.W. Bowersock, Oleg Grabar, and Peter Brown, editors. (An encyclopedic guide to the period 250-800 AD, with an emphasis on late Roman, Byzantine, Sassanian, and early Islamic culture.)
actually, that wasnt all acurate, i have read a few thing on the late Roman-mid Byzantine milatary, and here is some good stuff
Byzantium and Its Army 284-1081, by Warren Treadgold
The Late Byzantine Army : Arms and Society, 1204-1453 (Middle Ages Series), by Mark C. Bartusis
- I highlly suggest books made by a publisher called Osprey, lots of info, and lots of good pictures,and illustartions as well, here are some good titles for the era-
Romano-Byzantine Armies 4th - 9th Century (Men-At-Arms, No. 247)
by David Nicolle, A. McBride (Illustrator)
Late Roman Infantryman 236-565 Ad (Warrior, No 9)
by Simon MacDowall, Gerry Embleton (Illustrator), Gerry Embleeton (Illustrator)
Late Roman Cavalryman 236-565 Ad (Warrior Series, 15)
by Simon MacDowall, Christa Hook (Illustrator)
--Padma 
