The Wicker Man (1973/1998/2002)
Composed, arranged and recorded by Paul Giovanni and Magnet
The OST contains film score and songs written for the film, some of which are sung by the cast. That may sound like a bad idea, but if you've experienced the film, then you'll maybe agree they deserve inclusion. It was written in 1973, released in 1998 and re-released with superior sound in 2002 but with less tracks and minor changes elsewhere. Still, it's the better option if all you want are the songs in the best quality.
Musically it's dark and beautiful pagan folk that'll either lull or repulse you, but one word of warning: key tracks contain samples of spoiler dialogue, so it's best if you watch the film first.