Visit fashion shows, acting showcases and other industry events. Talent scouts are often in attendance and you can approach them to introduce yourself or ask them questions if it is appropriate to do so at the time.
Look up talent agencies online or in the phone book and visit the ones closest to you. You can meet specific talent scouts there and learn more about the process of how they do their jobs.
Skim through a book of talent agencies and send a photo, resume and cover letter to those that are in your field. Companies regularly produce books of current agencies, scouts and managers along with their contact information.
Speak to other models or athletes who are in your same field and see if they can refer you to any scouts. Scouts often intermingle with the people they're scouting and someone you work with can possibly help put you in touch with one.