*Try to find someone in your area who is an official.
*Find a mentor to help you. This was huge for me when I started.
*Your mentor or official friend will normally have last season's rule books that they can lend you so that you can study up.
*Spend some time with one of the books called the Officials Manual. That is real helpful for new officials.
The rule books for High School basketball come from your association who orders them through the NHFS. Their website is
www.nfhs.org. Dont bother ordering the books right now. You will get them when you join your local association. And, as mentioned above, you can get older copies from vetran officials.
But when you do get the books spend some time with them. Learning the rules is key.
*Practice your signals. In the mirror. With a spouse/buddy. Seriously. The sooner you get comfortable with proper signals the easier everything will be. Have a buddy of yours call out the foul or violation. For instance he calls out "traveling." Then you have to go "tweet" and then do a stop clock signal, then a travel signal, etc. Or he says "shooting foul" and you go tweet, make the foul signal, then indicate what it is, etc. If it is a foul, after your "call" it, go "report" it, which is the process of inidicating to the scoring table what the foul is. I know this sounds totally dorky, but it is really helpful for newbies. It is the number one suggestion that I have.
Good luck!