Please don't spam the forums by creating so many different threads. I have replied to two of your posts only a little over an hour after you posted. Please be patient. I'm sure someone will answer each of your questions in due time. Thank you.
The backdrops you are looking at, the psd ones, are photoshop specific backdrops. Any background that are basic photo backgrounds will work because they'll all be picture files such as tiff or png instead of psd. However, as far as photokey compatible backgrounds, check out tubetape.com. All their backgrounds are a mix of jpg and tiff.
I recently set up a store offering digital backdrops for sale and immediate download. I created the majority of the backdrops that FXhome offers, so much of the same content is available on my site here: