I have lemon grass, cymbopogon citratus, however if there's an asian market near you, buy 2 or three stems of lemon grass which look like they were cut a little long. This what I did. Mine didn't look like any of the base was left, but I stood them in a glass of water indoors/not in direct sun, and roots started about 3 weeks later. I suggest changing the water every few days, using non-chlorinated water. It'd be a lot cheaper than getting them mailed to you.

I do have c.flexuosus, thin-leafed lemongrass, which makes a lemon tea with great health benefits. If you can't find that locally, I can send you a plug:

If you can find lemon verbena, it's a great compliment to these, and can only be grown from cuttings. Bear in mind that none of these plants can stand even a little cold--one frost and they're gone, so best to grow them in pots, with lots of water.

Please ask if you have any questions.

Rick in CT