Natan,
Go talk to Jason at Seattle Kiteboarding. 206-372-5268. Kite size will depend on many variables, your size, wind conditions...etc. We started kiting last year and Jason is a great resource. Mainly, take lessons!! Practice with a trainner kite for hours. Don't handle a kite unless you know what you're doing for your sake and others. Learn all the safety requirements first and well. Rehearse them because in a scarry situation the mind can turn to mush. Also,- kiting is a lot of fun, Ken