I too would suggest volunteering at a rescue or something and getting some experience. Around here I don't think you'd have any chance of getting "hired" (as in a formal paying job) with no experience.
A wililngness to work, and work HARD as a volunteer will pay off. There's lots of kids/teens that want to hang around and do chores for freebies, but not a lot that really want to grunt and sweat. Find a barn, volunteer to work for free with no strings attached - just tell them you want to get started with horse, admit you're green, and ask what you can do to help, and then work your butt off.
Any decent barn owner will not only appreciate it, but if you're more than carrying your weight and really putting your best foot forward, should make it rewarding for you, if even just some free lessons.
If you get nothing in return other than appreciation and thank you's, honestly, even just BEING at the barn and working on the ground with the horses will teach you an immeasurable amount of skills needed to carry a formal job in the horse industry - you'll be amazed at how much you'll learn as the weeks and months pass even never having sat in saddle. Consider it an internship where you're gaining valuable experience as you WILL be learning a lot nonetheless. Smile, say thanks, and enjoy your time with the horses.
Ask for some basic ground handling guidance first (if you've never handled horses before) and then ask then which horses you can and cannot handle - bigger barns will have horses that are not
safe for beginners to handle, so it's important in the beginning to stay safe.
If you can volunteer this summer and get some experience under your belt and a good reference from the BO then I'd think the chances of getting a paying job at a more formal stable next summer would be greatly increased.