One generally orders them from a nearby fish stocking service (see the PB Resouirce Guide for examples).

If one desires (virtually all) same sex Tilapia (which could be an advantage for a small micro pond where no breeding was desired) you may be able to get them from a nearby aquaculture-for-food fish farm (there is one within esy driving distance of me where this is an option).

"Live like you'll die tomorrow, but manage your grass like you'll live forever."
-S. M. Stirling
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