Richie, first of all let me welcome you to the sport. Its a crazy world out there and you need to be able to understand the hype, and also the main things you need to start up.
As Supersol has already said, Goggle are the main item of equipment you need. Once you have boiught a decent pair of there, you will be sorted. There are usually plenty of spare markers at touraments and borrowing one is not hard, especially with a team like the Carrots. I know a few and they are a quality bunch of guys.
Now, are you sure its a Shocker that you want? Have you tried any other markers? The best thing I can suggest ot to buy "What Paintball Gear" and start reading as much as you can about the technical side of markers. It won't take long to get the basics, then all you need to do is to go out and try them. You will find that most players will only be too happy to let you have a go with their marker. Us Paintballers are helpful like that
Once you have got a preference for what feels right and what fits your style of play best, you can start looking for markers for sale. With a budget of £250 you are probabily looking at buying a marker that runs off CO2 instead of air. The added initial expense of getting a second hand marker with an air system is something you don't need when starting up. Cockers and Shockers run off both air and CO2, and are usually a good start for most entry level tournament players. Give them a look in, but the best advice I can give someone in your position is to try as much as you can out there, and make your own mind up. Remember, its alright listening to other people, but they don't have to play with the marker you choose and probabily have different playing styles anyway!
Good luck and just stick to what you feel comfortable with.
See you at a tourney soon
