German chamomile or Matricaria recutita. Get it at your local nursery or garden center as a plant. Or refer to one of the on-line retailers:

Richters
Horizon Herbs
Nichols Garden Nursery
Pinetree Seeds
Johnny Seeds

FataMorgana

If you have chamomile tea in your cupboard right now, sprinkle some over some potting mix or seed starter. There's probably seed in it. A few years ago, I was seed sowing inside and decided to mix a bag of chamomile tea into the starting mix instead of watering with the tea(to prevent damping-off). I don't remember how it worked for the DO, but I had chamomile sprouting like crazy in all my pots!

And just so you know, the part harvested for the tea are the flowers, not the leaves. Just a quick FYI.