Hi,
Thanks for saying you would like to support us, it is very much appreciated

As others have said, if you could let us know a budget to work too then that would help, but i'll throw some idea's about anyway
shampoo - I'm a big fan of Dodo Born to be Mild, available from £8.95 for 250ml, £16.95 for 500ml, and £26.95 for a litre
mitts - Can't really beat the Dodo Tribble Mitt for price and quality at £10.95
drying towel - A couple of options here, Dodo Juice Basics at £7.95 is an ok drying cloth, Waxamomo Deep Pile Cloth is very good at £7.95, or the Dodo Juice Double Touch is the master of drying and is £15.95
polish - I'm assuming you just want to add a good bit of bling to your motor? IT's easier to recommend this with a budget in mind as this and the wax can go hand in hand, i.e Dodo Juice Lime Prime and a Dodo Wax, Auto Finesse Rejuvenate and an AF Wax etc etc
wax As above really, could do with a budget idea.
sealant - Not always needed depending on what wax you go for, or you can bypass the wax and get a good sealant. Good sealants are Jetseal 109 (can also be used to protect your alloys), or Chem Guy's Blacklight, oh and there's some great pictures on our forum of Auto Finesse Power Seal being used.
interior products - Meguiar's Quick Interior Detailer is nice to use.
microfibre cloths - Depends on budget really. Poorboy's Mega Deluxe are our best selling microfibres though.
etc. - Wheel Cleaners, Alloy Wheel protection (kind od covered above), tyre dressings, foam lances......the list is endless

Hope that helps point you in the right direction, oh and as above, there is a special little discount code on our forum which was just a little thank you to forum users, but it's open to GolfGTI users too, anyone want to place an order, use the discount code - imfeelingfat - for 10% off

Chris