Dammit my PC crashed and restarted so TC's beaten me.
Get your car detailed from the start so you have a good base to work from. I didn't do this but wish I had.
As for doing it yourself, have a read over at detailing world on things like "two bucket method" "defect removal/paint correction" (can't remember what it was called and "machine polishing". All will give you a great overview of caring for your car properly.
If you want basic stuff from a place like halfrauds, I'd go for:
Shampoo: Meg's Gold Class shampoo
Clay: Meg's smooth surface clay kit
Polish: Autoglym Super Resin Polish. It's not abrasive so it won't cut the clear coat (which is what a proper polish would do) but fills in defects quite nicely.
Wax: Look for autoglym's HD wax if you can find it in halfrauds, otherwise things like meg's next gen wax and turtlewax's diamond ice waxes aren't too bad.
Glass: AG fast glass and AG glass polish (I use FG first, followed by GP)
Tyres: Meg's endurance gloss
exhaust: Autosol metal polish
For more expensive stuff, go to a place like cleanyourcar or elitecarcare.
Don't forget things like buckets, washmitts and drying microfibre towels. You can get microfibre cloths from tescos £2 for 2.