I'm sure this is one of the most discussed topics, but I am looking to start sprouting wheatgrass for juicing. These are the things I would like to know before I spend $X.

Where's the best/cheapest place to buy seed - and what variety?
" " for soil - I would prefer something organic or at least w/o chemicals
Any other tips such as supplements for the soil
Is a masticating juicer much better or will my juiceman jr centrifugal blade juicer be fine?

Thanks