Main Question or Discussion Point
How about his two books: Photons & Atoms and Atom-Photon Interaction? Are they basic?
Are there any other books contents of which are close to Cohen's QED books?Very good books, but not basic at all. Definitely graduate level.
If you want something more basic, then try Fox, Quantum Optics (OUP), Loudon, The Quantum Theory of Light (OUP), or Grynberg et al., Introduction to Quantum Optics (CUP).