I don't know how it is called, but the one at the corner of the Las Venturas Airport area beside the highway intersection is producing them.
However this one is always out of stock, so if you want to deliver appliances you'll need to deliver there first in order to get them produced.
If you asked this question because you see in /tpda that a lot of businesses are looking to get appliances, I'll tell you that this has a reason.
Nobody is delivering them because the industries that produce them are always out of stock, so they can't produce the appliances.
Businesses are in search of them because nobody delivers them, because none of the industries has stock to produce them.