A clay bar is worth investing in, although you only really need to clay once a year (or less if your paint doesn't need it). You'll need a soft one, but even so there is a chance of a clay bar marring soft Honda paint. You need a quick detailer for the clay, or make up a shampoo and water solution in a spray bottle.
If you want to keep to a budget, the first thing to buy is a decentish wash mit and some soft microfibre cloths, a microfibre drying towel helps no end (KKD Silverback is pretty awesome).
Shampoo, well any car shampoo should do, you can pay silly money for some. Snow foam is a great investment, but you'll need a pressure washer and will need to fork out £40 ish on a lance for starters. So maybe something for a later date.
Machine polishing is a big outlay too, £100 for a DA, probably another £30 or £40 for pads, then polishes. Something like Autoglym Super Resin Polish is OK by hand, it is a heaving filling polish, but you'll need to work it to get any results, wiping on and wiping off may add a little shine, but it won't do much.
Personally i've given up on polishes as Honda paint scratches so easily and i'll run out of paint if i keep on polishing it, so i've moved on to Glare. I use Micro & Pro, applied by DA on soft pads, but you can apply by hand. Spider is a heavier filling polish, so a three stage Spider/Micro/Pro should yeild some good results. Its not the cheapest, but it is pretty awesome. You can always wax on top if you fancy.
http://www.glare-uk.co.uk/glare-products
There is a GB on DW that may still be open
http://www.detailingworld.co.uk/forum/s ... p?t=383797 or use the 10% discount code.
You always get people throwing about a huge list of products or equipment, which require a huge outlay, and a special set routine every week! 
