I recommend the paper " An elementary core equivalence theorem" by Robert M. Anderson. It is a very short paper that contains a fairly self contained description of the basic models and concepts. You can then try to guess how to prove the existence of equilibrium based on some fixed point theorems or look at papers that Anderson quote. There are various more advanced models including models with incomplete informations ("rational expectation is a useful buzz word). There are also plenty of examples of market failure.
(I do not see why the recent financial crisis has anything to do with these models being less hot...)