Take a look at the guides published on Polish Bliss, I've found them really useful and helpful:
http://www.polishedbliss.co.uk/acatalog/car-care-advice.html
Understandably they use the guides to promote the products they sell but also give some indication of what type of product will work for your car so you can just search around and see what suits.
I started using Bilt Hamber products earlier this year and have found them to be great in terms of value, ease of application, overall finish and protection offered. I'm also a big fan of Chemical Guys and think their QD sprays are the best I've tried. I used to have a Technic grey Leon and CG Hybrid v7 detailer works especially well on the colour; it really gets the most out of the tone and metallic flakes.
My top tip would be take your time by removing as much dirt and dust off the car before you go near it with a mitt. Rinse from the roof and move the dirt downwards. I use snow foam and apply via a lance as part of my pre wash routine. The same goes for washing. I leave the lower bumpers, sills, etc until last and then do them wit a separate, older mitt.
I suppose a good starter shopping list would be something like:
1. 2 X big buckets
2. 2 X grit guards
3. Good quality lambs wool or similar mitt
4. Drying towel(s)
5. Microfibre towels
6. Wheel brush
7. Wash/shampoo
8. Detailing spray (drying aid/finishing)
9 Wheel cleaner
10. All purpose cleaner (check spec as you can save money using this in various ratio's to clean wheels, engine bay, windows, wheel arches, detailer etc)
11. A polishing compound/scratch remover, always handy for the small scratches that 'magically appear'.
12. Snow foam. A bit of a marmite thing but I always snow foam my car before washing, I think it makes a difference.
13. Tyre shine/dressing
The above should be more than adequate for your weekly washes and once every six months you may to do a full decontamination with clay and fallout remover. Followed by a thorough wash, polish, wheel seal and finally a coat of wax to seal everything. The products used for a 'big wash' appear expensive but you rarely use them so they will last.
It seems pretty expensive but if you just buy a few key items and add as you go along, it's not as bad. You can usually find most things on Amazon and I also tend to buy a lot from cleanyourcar.co.uk which also has a very helpful and friendly forum.
If you're sticking with Autoglym then I've found this place a good place to buy from:
http://www.uksupplydirect.com/c/54/...ish-manufacturer-of-quality-valeting-products
Hope this helps.