go to halfords where i think they still have a 3 for 2 offer on cleaning products. be clever and do several transactions so you buy three similarly priced items at a time (you get the cheapest item free)
buy a lambswool mitt, some meguiars microfibres (3 pack) and some meguiars applicators (2 pack of little foam discs)
buy some shampoo, either meguiars NXT, gold class or autoglym shampoo
buy the meguiars stage 1 and 2 polishes and either a NXT wax or similar.
buy the quick clay kit, if you can afford it. good as clay does make alot of difference and it also comes with bonus products.
buy either autoglym bumper stuff or meguiars trim detailer.
thats 9 products, so 3 lots of 3 for 2's so if you're clever you get more for your money. ie if you got a quick clay kit, NXT shampoo and the polish applicators in one transaction you'd get the pads free... bad! get the three most expensive things first, then next three, then next three... lot of effort i guess but worth it if you want the best savings.
then get two buckets and read the "two bucket method" and lastly get a drying towel from here:
http://www.elitecarcare.co.uk/product_info.php?cPath=64&products_id=196and thats a good start without spending a fortune.