I am very talented with art and computers and make very good websites. I have decided that i should start earning money for my work (however i'm only 15). So how do i start in creating a web design business

One of the minimum legal requirements for all businesses is that the company owner / creater is of legal adult age, which you are not, however you can legally contract your services out by freelance as a self employed minor, given that you do not need to have a separate legal entity (company) to work self employed. The first and most important thing to all business ventures is to establish an income, and keep cashflow coming in as greater in volume than the cashflow going out. If one of these fails, you end up in debt and can spend your life climbing out. In order to establish income, you must have people paying you, in exchange for goods or services, in your case web design. Web design clients can be aquired by advertising your services as available to the public, particularly targeting your audience, namely people who either do not have a web page, or have an old, pathetic web page. One way to advertise for free is to create a really good (your best ever) web page, and send a link in an email to organisation email addresses. This is called SPAM, and there are some laws against it, but it is so accepted in todays society that unless you SPAM the antiSPAM squad at the police department, with your name, address and phone number on the email, your probably going to be ok. you can also buy bulk (1000s) of current email addys for $10 on the net, but I suggest you use PayPal or something.