Some time ago I had come across a website which had the online version of a book about techniques dealing with the solution of sums involving binomial coefficients, and something with the word 'hypergeometry' if I am not mistaken. I now remember neither the book nor the website. I remember that it had a blurb by Donald Knuth, who said that it had been very useful and fast for him (or some such thing).
Does anyone know the resource I am talking about, and can you give me a link?
I think you mean the book A=B by Petkovsek, Wilf and Zeilberger.
Read Knuth's foreword.