Early blooms

I just got finished hacking off branches from my lilac bushes.

"You did what?!!! Don't you know that you won't get any blooms now?"

Relax. They will bloom—indoors. Just soak the branches in the bathtub for a couple of hours then set the branches in a large vase of water and wait. They will bloom wonderfully.

If you haven't forced a branch before, it's probably easiest to start with a tree that sends out flowers before the leaves each year: apples, cherries, or Forsythia.

There is a good description of how to do it here:
Forcing Branches indoors

If you want to try a your hand at a more difficult bush like lilac, I have found that giving the whole branch at least 3 hours of soaking seems to make a real difference between success and failure.