Okay, that's hilarious! Connie Willis's most recent book, Blackout is part one of two, except it doesn't make that clear at all in the front matter (there's one point in I think the acknowledgments that in retrospect indicates it, but not clearly enough!) and so you get to the end and are literally stranded in the middle of the story with the characters. So I would highly recommend waiting to read it until after part two, All Clear, comes out in the fall. I guess I just assumed those points went together! Oops.

Everything Connie Willis has ever written (that I've read, anyway -- I haven't yet read her stuff with Cynthia Felice, and I'm not sure I've read all the short stories) is fantastic. Doomsday Book is probably still my favorite, but it's a close thing. They all have incredibly different atmospheres, though: Passage is probably the closest to Doomsday Book, To Say Nothing of the Dog is another Oxford Time Travel novel (so is Blackout) but is pure madcap farce, Bellwether is quirky and stylized and endearing, and Remake is basically cyberpunk with Pat Cadigan sorts of themes (it could perhaps be considered the weakest of her novels, but I enjoyed it anyway). I envy you for getting to read them all for the first time!

I may have to check out Selma Lagerlöf -- intriguing!