Hi Weiss...for anything mounted, I'd say Andy's! They have a great selection, good prices and are vey helpful.
You can see pictures of Phal lobbii, purchased there by 4of us for our current project in the Chat Project section of the forum's Gallery.
If you order from them, please mention Orchidboard
It depends on what Phalaensopis species you are looking for. Almost all Phalaenopsis are epiphytic, but they aren't normally mounted... like Sue said, Andy's Orchids has Phal. lobii mounted.
All most all Phal. species are easy to care for when mounted, it is just finding a source of pre mounted Phalaenopsis is the hard part. Some species don't grow well when potted or even put upright, they have to have similar conditions to the arching of a Gastrochilus. I would suggest getting a smaller plant of a Phalaenopsis species, and then mounting it to a piece of cork.