There are several vendors from which you can order spores and supplies from. This link underneath leads to a list of sponsors of the Shroomery.
Questions regarding specific vendors can be researched in the Sponsors forum.
All of the listed vendors are reliable, and have a positive reputation. When you decide what it will come down to is who has what you're looking for, how much you're willing to spend, and other personal feelings you may have about a vendor in particular.
