I added a list of the seeds I use the most in my designs to the spora website. I got the information about the seeds from this gorgeous book that has just been published in Brazil:
Sementes Ornamentais do Brasil / Ornamental Seeds of Brazil, edited by Francisca Portinari Leåo, published by Reler Editor Ltda, Rio de Janeiro, 2008.
It is very nice to have an "official" guide to the seeds. My experience is that people tend to be very creative when they don't know the name of the seeds they are selling!
Check it out:
www.sporadesign.com