Andy has hit the nail on the head, I reckon you don't need to spend big wonga to get a great finish. If the car hasn't been done for a long time or ever the following will give good results
Wash - any old car shampoo
Clay - I use Bilthamber
Polish - Autoglym Super Resin Polish
Wax - Autoglym Extra Gloss Protection or the one I'm using at the moment Bilthamber Autobalm
If you're feeling lazy then you can substitute the polish/wax steps for a single hit of Autoglym Ultra Deep Shine which does give a fantastic finish. haven't used it for a while but the results were fabulous on my old Alfa 156 in Alfa Red.