You get a point every odd level. You should have gotten one at 51.
The balance of the points come from:
1) Completing deeds in Helms Deep
2) Completing your class deeds by using skills
3) Doing your level 58 class quest
5) Doing the 3 level 39 class deeds
6) Doing your level 50 class quest
7) Completing Volume 2 - Books 1-6
8) Reaching Kindred with the Iron Garrison Guards which will allow you to buy and use your class book.
Unless stated otherwise, all content in this post is My Personal Opinion.