Learn about magic in general. Go to your local bookstore or library and read books that tell you the basics of the art. This will teach you important principles like the materials involved, props, angles of vision, and dramatic flair. These principles will be important stepping stones to learning how to perform fire magic in particular as well as magic in general.
Go to a local magic store. Hang out at the store, observe the tricks performed while perusing the store, and talk to the store workers. They will be only too happy to point you in the right direction for material that will teach you about fire magic. If they do not carry the items themselves, ask to see if they can order it or where you can purchase it yourself.
Research fire magic online. Some basic information is available for free. A quick search will show you lists of names of magic tricks, as well as places to purchase the tricks. Purchase as many magic tricks as you can, and practice mastering them.
Find a teacher. The best way to learn fire magic is under the instruction of a tutor. Go to your local magic store and ask if anyone is available to teach you. Join a local magic club and ask around to see if teachers are available. Keep your eyes open for performances of local magicians, and stay afterwards and ask them for there availability. Even if they are not available to teach you themselves, they might be able to point you in the right direction.