It seems their is a new syllabus for every examination board every year, but ultimately GCSE Mathematics has been the same material for years. So get your hands on any GCSE papers you can for practice. Here are some past paper solutions to help you revise.
Random collection of questions requested via twitter and facebook
I am working on tutorials covering all GCSE topics, for now to whet your appetite check out:
ALGEBRA:
Algebra – Creating, Manipulating and Solving Linear Equations
Quadratics – Factorising, Solving, Sketching
SHAPE & SPACE:
Circle theorems – Tutorials and 20 Questions
Dimension Theory – Is a formula length, area or volume?
Or try:
All tutorials (not sorted in any manner)
mathormaths.com 