It's from a husband/wife duo called "Fleming and John". The first link below has some info on them (you have to scroll down a bit). You used to be able to download the complete song from their website, but unfortunately, their website appears to be down now.
http://www.mistletunes.com/rockpop00.html
Found this link to the music, which has edited the recording a bit (and doesn't credit them). In the original that you could formerly download from their site, it started off with a slow intro that lulled you into thinking it was a traditional rendition, then sequed into the "Misty Mountain Hop" part.
Fleming and John
It's from a husband/wife duo called "Fleming and John". The first link below has some info on them (you have to scroll down a bit). You used to be able to download the complete song from their website, but unfortunately, their website appears to be down now.
http://www.mistletunes.com/rockpop00.html
Found this link to the music, which has edited the recording a bit (and doesn't credit them). In the original that you could formerly download from their site, it started off with a slow intro that lulled you into thinking it was a traditional rendition, then sequed into the "Misty Mountain Hop" part.
http://www.kcfx.com/airstaff/zep_player.htm