TBH, given this is your first venture into detailing, I would suggest the Megs 3 stage as you can get it from Halfrauds. Give it a wash, clay, polish and wax. That should get you looking good enough for starters. If you want to get into it more seriously, then get onto the traders (Envy, i4detailing or even Polished Bliss). They will sort you out
From Halfrauds I would get:
Megs Clay bar kit - £18 ( http://www.halfords.com/webapp/wcs/stor ... yId_165527 )
AG Starter Pack - £10 ( http://www.halfords.com/webapp/wcs/stor ... yId_165671 )
Megs Stage 3 wax - £8.50 ( http://www.halfords.com/webapp/wcs/stor ... yId_165527 )
The AG started pack gives you some samples of wash, polish (body and glass) and tar remover which is good for getting off stubborn bits that clay wont shift. Can be substitued for Megs Stage 1 + 2 but that costs a bit more. Depends how into it you are.