Hi,
Check these two pages for info on "basic polymer clay tools" and suggestions for where to buy them... for many polymer things, you can get along fine without any "special' tools:
http://www.glassattic.com/polymer/tools_Dremels_worksurfaces.htm
(... click especially on Beginner Tools and Work Surfaces and Brayers...)
http://www.glassattic.com/polymer/cutters-blades.htm
(this page covers blades and other types of "cutters" including shape cutters)
Having a pasta machine is really a good idea for polymer clay, but it's not essential. There are suggestions for getting cheaper ones on this page, along with a lot of the cool things they can do:
http://www.glassattic.com/polymer/pastamachines.htm
For some things, a clay gun can come in quite handy too, but is not necessary at all:
http://www.glassattic.com/polymer/claygun.htm
Since you're in the UK, you might want to check out the suppliers (for polymer clay and tools) outside the US too:
http://www.glassattic.com/polymer/supplysources.htm
...this page also has info on ordering things from the US from outside the US (click on Non-USA for both)
HTH,
Diane B.