Richard Bernstein is currently the best writer on pragmatism. I recommend his book recent book The Pragmatic Turn as a good introduction to both classical and contemporary pragmatism (Hilary Putnam recently praised this book as being one of the best books written in the 21st century on pragmatism). He writes incredibly clearly and has an excellent knowledge of just about every area of philosophy (from Ancient to Modern, Kant, Hegel, American Pragmatism, 20th Century Continental, and Analytic philosophy). If you are interested in the pragmatic spirit of inquiry, two of his earlier books are also worth reading: Praxis and Action and Beyond Objectivism and Relativism.
George Herbert Mead is a neglected figure in the historical pragmatic tradition that is becoming increasingly popular, especially in other disciplines like sociology. His social theory is similar to those of Hegel and Wittgenstein. He was heavily influenced by James.
If you are interested in contemporary pragmatism (i.e. the analytic revival), then I would look especially at Hilary Putnam (basically everything he wrote after Reason, Truth and History), Richard Rorty (although his version pragmatism is extremely controversial and I would also look at critiques by Davidson, Bernstein, Putnam, and Brandom), Robert Brandom (epecially his essays in Tales of the Mighty Dead), John McDowell (Mind and World is difficult, but is definitely a contemporary classic), and Jurgen Habermas (who combines pragmatism with critical theory and other continental traditions).
Hope that helps!