I love Love LOVE my needle threaders. Both my Brother and my Singer have them, and they work GREAT. I'm so darn near-sighted that I can't see the needle hole well.
I can't really help other than to say that I have a really hard time seeing the hook thing, too, but it's there. Make sure you hold the thread up but do not put ANY tension on the thread. I've unthreaded my needle several times before I figured this out. :oops:
Anyway, it would be worth it to me to take it back if the hook is missing. It always took me several minutes to thread needles with my old machine. My new ones, it takes about 5 seconds. :D