Australian singer Angie Hart was quite a favorite on the Buffy series. One song was written specifically for the show, and her group Splendid, made up of Hart and her then-husband Jesse Tobias, played two songs at the Bronze.
The unreleased song "Tomorrow We'll Wake" is in the episode "Forever" and plays during a scene with Xander and Anya.
"I Only Have Eyes for You" is episode 19 of Season Two. The plot is about a ghost of someone who killed their girlfriend and committed suicide.
"Charge" and "You & Me" are played at the Bronze by Splendid, with vocals by Hart.
"Once More With Feeling" in Season 6, episode 7, is of course the musical epicenter of the entire series, and a tour de force by Whedon - it should have won an Emmy, alas. What's amazing is that it combines elements of Broadway musicals, old TV themes, dance numbers, and all by actors who weren't known for their singing ability. It's really my favorite episode, and Whedon has mentioned it as his also, which isn't surprising given his later success with "Dr. Horrible's Sing-Along Blog."
From The Buffy Trivia Guide
Joss Whedon, the show’s creator, wrote the music and lyrics for Once More, With Feeling himself with help from Buffy composer Christophe Beck and Splendid’s Jesse Tobias. It took him three months to write the episode - over the summer when he was supposed to be taking a break. The episode was is the only one of season six which Joss wrote or directed.
Buffy composer Christophe Beck spoke to the Bronze posting board about Joss Whedon’s talent: “[He] came up with lyrics, melodies, the underlying chords/harmony, as well as general stylistic direction for each of 16 musical numbers. The songs started out as four-track recordings Joss made himself. I co-arranged and co-produced the songs with Jesse Tobias of the band Splendid.”
Once More with Feeling took four months in total to write, film, and produce.
Angie Hart sang back-up for actress Amber Benson as Tara in "I'm Under Your Spell."
The collaboration continued in Episode Seven of Season Seven (magical numbers) with the song "Blue" in "Conversations with Dead People," a joint writing venture of Hart and series director Joss Whedon. It's probably my favorite song of the whole series, and just captures Buffy alone again at nightfall - just fantastic lyrics. It's found on both US and UK versions of Radio Sunnydale:
