Chaz,
Your post might be a bit out of season for a request of canna seed. I suspect that any grower has likely already planted any seed they collected from the past year. Few people would likely have seed production available this early in the season. Hopefully someone has responded privately. You might Google "canna seed" and find a supplier with seed still available. Good luck. Kent

I wouldn't buy commercial seed. It may be old and germinate poorly. Fresh seed is a much better option. If you are averse to stealing some from plants you see in the park - now is a very good time btw, I don't know what Kent means about it being out of season - you could also always go and ask nicely if you could have some from someone's garden. Most people are flattered by the request and very few people bother with the seeds anyway. You must remember, however, you can't obtain named varieties from seed as they are hybrids and will not come true.