Mark Armour and Daniel R. Levitt wrote a book called In Pursuit of Pennants: Baseball Operations from Deadball to Moneyball and they followed that up with a couple of blogs: The 25 Best GMs in Baseball History and one currently running, Important Moments in Team Building. I would recommend this latter. It currently has 18 of the planned 25 discussions posted (the links to all may be found on the link provided above).
1. The Reserve Clause (1879)
2. NL-AL Peace Agreement (1903)
3. The Federal League War (1914)
4. The Sale of Babe Ruth (1920)
5. The Trade Deadline (1922)
6. The Anti-Trust Exemption (1922)
7. Branch Rickey’s Farm (1925)
8. The Farm System Goes Legit (1932)
9. Chasing Pennants in Boston (1935)
10. Jackie Robinson (1947)
11. Bonus Rule (1953)
12. Interleague Trading (1959)
13. Amateur Draft (1965)
14. Collective Bargaining Agreement (1968)
15. Free Trade (1971)
16. Binding Salary Arbitration (1973)
17. Catfish Hunter (1974)
18. Andy Messersmith (1975)
1. The Reserve Clause (1879)
2. NL-AL Peace Agreement (1903)
3. The Federal League War (1914)
4. The Sale of Babe Ruth (1920)
5. The Trade Deadline (1922)
6. The Anti-Trust Exemption (1922)
7. Branch Rickey’s Farm (1925)
8. The Farm System Goes Legit (1932)
9. Chasing Pennants in Boston (1935)
10. Jackie Robinson (1947)
11. Bonus Rule (1953)
12. Interleague Trading (1959)
13. Amateur Draft (1965)
14. Collective Bargaining Agreement (1968)
15. Free Trade (1971)
16. Binding Salary Arbitration (1973)
17. Catfish Hunter (1974)
18. Andy Messersmith (1975)