Going on from what fish said and a few others.
I have pm'd you back with the questions you asked as well.
First off you need to think of your catchment area from my knowledge liverpool/wirrel doesn't have any teams so they except you and some other team i cant remember the name of it.
You have to think about what teams want as well, you need to attract teams so you need some thing that other people haven't got or have but yours is better.
First off a supair field, you are going to need a full pro MS field its the only way to get teams down, most tournaments now have full ms field even for 5 man, so i would be a waste of money with just getting a tinpot 5 man field which is about 3k any way.
Next off you need a compressor, you need some thing that will handle about 100 people at a time, it might seem excessive but it means you machine wont be running all day and will take less maintenance as well, one thing i would say on this which we went the wrong way about is dont try and get them for cheap, go to hpac who will sort you out and keep it running for you, we made 2 mistake's by trusting people who we thought would help us out when at the end of the day the sold us a crap system and told us lies which could of endangered peoples safety as well.
Netting, you can get normal debris netting from any were but you need the good black fruit fly netting which is a lot of money but will not let you donw and will last a long time.
Bit and bobs, you need to get decent blowers which are about 130 quid a pop, getting ones from b&q are just a waste of time because the amount of us they get at one time we took back about 7 in a year.
Field cleaning you need to make sure you have a supply to water even if it getting it from a tap.
Right the hard part, you need to talk to your team about this and see if they are up fro helping out, i have been lucky with the great guys on our team but it gets to people being there at stupid o'clock then staying till its dark in the rain snow wind and what ever else, its a real hard slog mate it really is the only reward you get from it is when your team does well from the amount of training you do and that the only thanks i ever wanted was for our team to do well.
This is only the basics and every one else will have there own opinion on this matter and this is just mine but i ran it for 5 years and we did ok.
One big bit of advice i would give you is Don't listen to people who always say "yeah count me in" and all this cause it seldom is the case dude.