The collectors' edition of WHR has an interview with her about the recording of Shell and Half Pain for the series. It's very interesting to hear what she has to say about the songs. :) I don't know if she does any other professional recordings, unfortunately.
Last.fm really needs a way to differentiate between artists with identical names. The Japanese artist Bana who performed the [i]Witch Hunter Robin[/i] OP/ED themes is clearly the more popular of the two going by the scrobbled stats, yet only the Cape Verdian artist is listed with tracks, albums and videos. :(