Don't just send any ol' photo to a magazine. Send one that matches the style of the magazine. Alot of girls share with me the frustration of not hearing back from their submissions but maybe the problem isn't the effort they are putting it, maybe it is their photos.
Are you sending photos that don't intrigue the photo editors? Are you just randomly sending a photo without thinking, "does this photo fit the magazine?"
Magazines get many submissions, and usually work with agencies, before the model. But it is worth a shot, especially for smaller magazines to submit yourself.
To get ahead, think small first. Build your portfolio, build your experience:
Try submitting to a local magazine even, maybe you don't have a modeling agent or modeling agency but you can still market yourself if you have good photos, or if you live in a small town look into the newspapers, try to get intouch with the editors, and of course be selective about the photos you send!
You can e-mail editors but also direct mail is a good idea as well.
Think inventively, think about realistic ways you can get tearsheets and a resume rolling.