I have a two year old Tacca chantrierii which has produced several blooms. Where would I find the seeds of this plant?

I know nothing about this particular plant,but there are people on this site who grow it, so hopefully someone may add something.
What I do know, though, is that, for a flower to turn to seed, it has to be fertilised, usually by a pollinating insect like a bee or similar. So, as you've got no seeds, I assume the flowers were either not pollinated, or the plant produces sterile flowers anyway.

I expect that it needs some highly specialised pollinator, like a hummingbird or exotic moth. Thompson and Morgan sell more plants, that may be the easiest way to get more! Apparently you can also divide the bulbs.