If you're looking to get into a big D1 University track program, I'd say consistently running sub 10.6 FAT in the 100 would be in order (that's if your looking for a scholarship). Especially in America, there are a ton of talented kids at the high school level, so it takes a lot to get a full ride somewhere. Walking on would probably be easier at a D1 school, or even considering going to a D2 or D3 school where you can be more competitive. As for the times necessary at those levels, I really dont know. Consistent sub 11s maybe?