I am looking for a good introductory book for Seiberg-Witten theory. The only textbook I have now is Morgan's "The Seiberg-Witten Equations and Applications to the Topology of Smooth Four-Manifolds". This book is self-contained and concise and definitely a good book, but I am lost before section 4 "Seiberg-Witten moduli spaces" due to my poor background.
I would appreciate it if you could introduce me a good textbook or introduction paper for this subject. I am also happy if anyone knows a good reference for spin bundles and Clifford bundles. I am aware of the book "Spin Geometry" by the way.
My advisor Michael Hutchings and his advisor Cliff Taubes wrote a brief note on this which is where I definitely suggest starting: http://math.berkeley.edu/~hutching/pub/tn.pdf
If you're getting stuck around the "moduli space" part, then I suggest taking a step back and understanding the general picture of counting pseudoholomorphic curves, from McDuff & Salamon's classic book on Symplectic Topology.
If this was enough overview, then the next step (and perhaps the last that you'd need) is Salamon's Spin Geometry and Seiberg-Witten Invariants, which deals with all the required background plus the thorough development of the theory, packed with a ton of useful/friendly info.