The folks at Sony Masterworks have just issued a four-CD set called Stephen Sondheim: The Story So Far. You get a booklet and all sorts of neat historical stuff, and then the CDs contain a kind of biographical survey of Sondheim output, chronicled through tracks from his musicals, interviews and previously-unreleased music tracks. I haven't got mine yet but it sounds like one of those "if you're at all interested in Sondheim, you gotta buy it" deals. To order, click right here.
In the meantime, the Sony Masterworks folks are favoring us with a four-month series of weekly podcasts on Sondheim's life. Three installments are already up on the website with many more to come. Give a listen.