Tonight's eclipse is "penumbral." In other words, the Moon will pass through the pale outskirts of our planets shadow (the penumbra) rather than directly through its red core (the umbra). Graphic artist Larry Koehn has created an excellent animation of the event.
The best time to look is Friday night around 07:44 p.m. Eastern Time (00:44 UT Saturday). That's the time of maximum coverage when Earth's shadow creates a clear gradient of light and shadow across the lunar disk. Check out this global visibility map to see if you are in the eclipse zone:
www.spaceweather.com