For better or for worse, Cosmology isn't like E&M where there are just two dominant books (Griffiths, Jackson).
Some options are:
Weinberg - Cosmology
Quite difficult on the maths side, but amazing insight that only Weinberg can bring.
Kolb & Turner - The Early Universe
Authoritative book on the early universe. Rather specialized and high level, so if you want an overview of cosmology it's not great, but if you just want to know something about the early universe, they'll tell you about it.
Narlikar - An Introduction to Cosmology
Pretty well-written and easy to read, but I think he spends to much time on alternative cosmologies.
Dodelson - Modern Cosmology
Lots of people seem to like this one, although I haven't looked at it much myself.
Mukhanov - Physical Foundations of Cosmology
I found this one a little too hard, based on the level of math. Lots of other people seem to like it.
Ryden - Introduction to Cosmology
Very fun and easy to read, with no hard math... I like this one as a first exposure to cosmology.
Coles and Lucchin - Cosmology
I really like this one, although not many others seem to. Well written, good level of difficulty, good mix of theory and observation, structure formation is presented in a very accessible manner.
Peebles - Principles of Physical Cosmology
A length overview of cosmology by one of the legends in the field. I don't care much for his writing style though.
My recommendation: Try out Coles and Lucchin, and take a look at Dodelson, or if you think you can handle the math, go for Weinberg.
Also Leonard Susskind has a series of online lectures on Cosmology from Stanford (Itunes Store -> The Theoretical Minimum), although I find that he goes painfully slow. There's still some insight to be had though.