Look up the USDA Plants Database. It provides a lot of information on where you might find all kinds of plants. It has maps, and for some species the data is down to the county level. Ŕlso indicated is whether the plant is introduced or not.
Searching 'Prosthechea USDA Plants Database' will lead you to:
Plants Profile for Prosthechea (appendage orchid)
Note that if you track the symbols, to will see that the genus is native to the lower 48 states, Puerto Rico and US Virgin Islands. How weird is it that the common name is 'appendage orchid'?