So far as I know, Jim MacLeod wrote The Wee Laddie himself, which would explain why it's not available on the net yet.  There's always a degree of confusion when people (it seems usually to be an American habit) refer to "songs" rather than "tunes"; as a general rule, it's best to describe a dance tune as "a tune" and a song (a tune with words attached to it) as "a song".  Makes it easier for us to help!

Malcolm