Matt,
Been there got the T-shirt!
I had so much advice from here that it helped fine tune what I actually needed as opposed to what I didn't.
I was fortunate enough to inherit some nice airbrushes and a compressor(Iwata/Sparmax)
Before that I got a cheap Chinese
airbrush compressor combo off Amazon.
This came with a small compressor and three airbrushes, 2 x gravity feed and 2 x bottle brushes (which I never used).
For £70 it was a bargain and did the job!
Next was paint.
Wow, so many variations...I couldn't get on with acrylics so defaulted to enamels which were very good although not so the fumes!!
Eventually I bit the bullet and ventured into the world of Vallejo 'Air'.
I've not looked back, my spraying is easy and results never disappoint, no thinning, straight from the bottle and a good colour range.
Of course the best advice I can give as a newcomer is what everyone else told me...PRACTICE!
Good luck in your final decision, it's a nice feeling when it all comes together.
Del