Bucks music group is not music library, but rather a overall company such as EMI. Standard Music Library, is the production music library. http://www.bdimusic.com/ is the publisher.
GMTV is not on any public website to allow you to hear it.
Bucks publish the music, the actual recordings are not library tracks & were made for GMTV. Bucks just publish it and basically say who can use it and when - I think they have some recordings, might be worth emailing them though I would not hold my breath!