Changing a timing belt is a big job, and if not performed correctly can damage your engine. So, I recommend you get a very good repair manual. It's real easy now that they're available online. To be better prepared when replacing the timing belt, read up on the job before touching the car so you'll better understand what you're in for and what special tools you'll need.
Try http://bit.ly/mitchell_repair_manuals_online and you can have one in minutes, for less than $30.00.