If you want to do walk-ons or secnario games then go for an A5 as a cheap first marker, if you have the budget look an Eclipse Etha or a Tippmann Crossover
If you are looking to play Tourniment you will need an entry level electronic marker such as an invert mini, again if you have the budget an Eclipse Etha will also be fine.
My advise would be spend money on a decent mask £70+ the mask is more inportant than the marker when you are first starting out, steamed up mask will put a damper on your day
rob http://www.universal-exports-pb.com/
I've just started out in grand scheme of things, I am in dereham and go to the walk ons at combat. Also have for sale a few markers a Dye NT11, a BT tm 15 and a Sierra one.