The k.u.k. Austrian - Hungarian army: Books & Links
The most interesting book I found is
Gerd Holler
...für Kaiser und Vaterland
Offizier in der alten Armee
Amalthea-Verlag Wien 1990, ISBN 3-85002-287-0
Besides the personal history of Dietrich von Hermannsberg, who joined the artillery in 1786 and retired in 1849, the book goes into a lot of detail, describing the schools, customs and major campaigns of the army.
On the first World War, the best book concerning Austria-Hungary I found is
Manfried Rauchensteiner
Der Tod des Doppeladlers
Österreich-Ungarn und der Erste Weltkrieg
Styria-Verlag 1997, ISBN 3-222-12454-X
Manfried Rauchensteiner is one of the most famous military historians and the director of the Museum of the history of the army in Vienna.
Another interesting book containing a lot of pictures about World War One is
Hans Magenschab
Der Krieg der Großväter 1914 - 1918
Die Vergessenen einer großen Armee
Edition S 1993, ISBN 3-7046-0115-5
Hans Magenschab is journalist in Vienna and was editor-in-chief of "Die Wochenpresse".
Out of classic literature, you can get an inside view reading
Joseph Roth
Radetzkymarsch
Kiepenheuer & Witsch 1989, ISBN 3-462-01981-3