Where to buy high grade wheat grass powder?

I've been buying my powder on ebay but I don't know what quality or grade it is. Is it better to have a combo wheat grass with another such as Kamut? I'm a little overwhelmed with all the info out there and any help would be appreciated.

This thread if for solely of the powder form. Please do not try to convince me of why I should organically grow my own grass and why live grass is better than dead powder, etc. I made a choice to stick with powder.

Thanks for your time.

FROZEN...freeze dried or powdered....but

SWEET WHEAT make a good product.....consistantly.

FRESH!!!! is best.