Karen is of course absolutely correct in her listing of helpful books. But you might also try ORB at: http://orb.rhodes.edu/textbooks/palindex.html Dave Postles has an online course in paleography that should help. For me, the real key to mastering the art of reading manuscripts is practice, and he provides the perfect vehicle -- interactive photos of real manuscripts, over which you can move your cursor and see at the bottom of the screen the transcription of each word. Deciphering the abbreviations is just a skill, one you master by looking at lots and lots of them. Enjoy!