I purchased a "tiny razor" by Noxzema you can find them in the beauty section of a store like Walmart or even a grocery store (found mine in Publix). They're really cheap and come 3 in a pack.
You can search for "Noxzema Eyebrow Shaper" on Amazon and it should come up.
They're really easy and painless to use. Just be careful because any sudden movement can shave off too much. This is what I use because I hate plucking. It comes out just as nice!