The consumables (tips, shroud, wire) as well as the swan neck, new gas valve and the regulator I got from weldequip on the mig welding forum:
http://www.mig-welding.co.uk/shop/
He's a very friendly guy and if you're not sure what you need then give him a shout and he will know what you need, he really knows his stuff.
If you are thinking of buying a brand new welder then get it from him as he is highly recommended.
I managed to get my welder (used) from a bloke on ad trader. It had a few problems like a sticking gas valve and a broken swan neck, (cost £30 to get new parts), but i guess that's what comes with buying something which you don't already know the ins and outs of, however I'm glad I bought it.
I bought myself an autodarkening helmet for £40 from ebay, its a Parweld helmet and comes highly recommended, I've always used on from the beginning and it makes your life a lot easier, as you know you're going to be welding in the right place. I leant it to HandyAndy just as he was about to finish his chassis, he really wished he bought one to start with

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Don't get me wrong, the costs do add up, however once you are setup, the welder keeps its value. I am still on the same reel of wire, the same tip, same shroud and my second pub sized bottle of CO2, i've done quite a lot of welding with it and it certainly beats my £40 arc welder from aldi

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