Bit late to this thread but I can offer a little advice as I was recently in the same position as you Crushy.
The problem I found with this topic is that allot of the advice was US orientated (lucky buggers seem to have a hobby superstore on every street!) so it can be difficult to obtain the stuff advised either nationally or locally and at what I would consider to be an affordable price.
I also ummed and arrred about what to get for ages and looked into a few other threads on Dakka as well as more general searches.
I decided to buy a cheap compressor kit that came with two airbrushes (both dual action, one gravity and the other siphon) and 3L tank. A 16L tank is way too much
btw unless you have a permanent position to house it and use it in - i.e. workshop/garage etc.
I bought mine from RDG Tools
http://www.rdgtools.co.uk/cgi-bin/os000001.pl?ACTION=Start. I found this lot after allot of searching. There quite a few traders selling cheap compressor kits on the web and eBay in the
UK and I plumbed for RDG Tools after doing a bit of research on them (I have trust issues what can I say!).
While they have a webstore and an eBay store, I called them up and asked for a few changes with the stated kit (I upgraded to the cased compressor and added some cleaning kit) and they delivered it to me the next day!
Lets be quite clear what I got was Chinese (probably) knock-offs of I believe Badger airbrushes. But a quick check of the kits and it is all A1. While I appreciate that you will get what you spend with airbrushes, there is no need to splash out on an Iwata set up while you are starting out. My whole set up cost me £119, the equivilent brand set up would cost £300-500. I think that this is the best approach while learning, I can get quaility stuff as my skill developes (or not

).
I have been up and running with it this for a couple of days and have learnt numerous quirks of airbrushing and finally took the plunge of spraying one of my tanks. I am really chuffed with the results and throughly recommend that you take the plunge!
Good-bye hours of brushwork!