The Human Drama is named after the soulfully mellow goth band Human Drama. I hadn't planned on naming the series after a band, but after the first few stories had been written, and all of them had titles taken from Human Drama songs, I realized that it was painfully appropriate. Willow and Cordelia have a life of trouble from the moment they first realize their love, the human drama continuing upon its way.
You can purchase the CDs at CDNow.
The World Inside is their first album. This one has "This Tangled Web" on it, plus many more extremely good songs. But "This Tangled Web" is the best.
Songs of Betrayal is a single CD, or, at least, the one I own is, but there are now two separate volumes for it. Volume 1 has "This Forgotten Love", "Forever", "Where Our Weakness Lies", "Let The Darkness In", and "As Love Comes Tumbling". Volume 2 has "Remember Well" and a variation on "This Forgotten Love".
There's also a compilation called In A Perfect World, which should have all of these songs on it, but CDNow doesn't have the track listings.