Where can I find size 17 4E baseball cleats for my 15 yr. old son?
BigShoes.com and XLFeet.com both have cleats up to size 18. That's an uncommonly wide foot your son has, and I don't know if they carry it.
Wouldn't you have more luck "asking" this at a sporting goods store than Y/A? I highly doubt that anyone (else) on here has a "15 year old son with size 17 feet".