Sites

Difference Equations to Differential Equations (Popularity: )
http://math.furman.edu/~dcs/book/
By Dan Sloughter. Published in PS/PDF with applets under GPL.

Journal of Difference Equations and Applications (Popularity: )
http://www.tandf.co.uk/journals/titles/10236198.asp
(Routledge) Table of contents from vol.8 (2002). Full text to subscribers.

Difference Equations and Discrete Dynamical Systems (Popularity: )
http://mywebpages.comcast.net/dedds/
A web-based newsletter.

Symmetries and Integrability of Difference Equations (Popularity: )
http://www.esf.org/euresco/04/pc04185/
EuroConference on Analytic Difference Equations, Special Functions and Quantum Models on the Lattice. Helsinki, Finland; 19 - 24 June 2004.

Books Corner (Popularity: )
http://mywebpages.comcast.net/dedds/debooks.html
Reviews and pointers to books.

The Math Forum (Popularity: )
http://mathforum.org/library/topics/difference_eq/
A compilation of sites relating to Difference Equations.