Coleman, R.; Mazur, B. The eigencurve. Galois representations in arithmetic algebraic geometry (Durham, 1996), 1–113, London Math. Soc. Lecture Note Ser., 254, Cambridge Univ. Press, Cambridge, 1998
A seminar page from Essen with lots of references.
http://mathoverflow.net/questions/75144/global-applications-of-eigenvarieties
nLab page on Eigencurve