LPTV is working in New York. It is most successful where the local cable company carries the signal, but because the FCC does not force cable companies to carry signals, most don't. It does some original programming, but mostly relies on huge stockpiles of old movies. There are other smaller networks that appear on cable such as UPN, but these are in turn owned by other, larger media companies. But the local station is the heart of television, and where we'll take up on Friday.
Networks exist to provide programming to the local affiliates.