For an overall excellent text on networking, I recommend:
Computer Networks, by Andrew S. Tanenbaum
This is THE classic networking text. Tanenbaum takes you through every layer of the OSI Reference Model (and hybrid internet model) and discusses theory and protocols used in each layer. The Network Layer and Transport Layer chapters discuss IP and TCP extensively (each chapter is over 100 pages).
This is the book most everyone uses in graduate and undergrad computer networking courses, and is also a a good general reference.
If you only want information on TCP/IP, check out:
Internetworking with TCP/IP Vol.1: Principles, Protocols, and Architecture, by Douglas E. Comer