Maybe with the new season surge we can pick off some of the remaining unanswered lines:
3) Of course the house is haunted.
Hint: This one is from an anthology, not a novel.
8) When Sean Devine and Jimmy Marcus were kids, their fathers worked together at the Coleman Candy plant and carried the stench of warm chocolate home with them.
Hint: This book is not SFF, is set in Boston, and was made into a movie that won two Academy Awards.
11) It's about sex, and cruelty, and forgiveness.
21) Towards the end of things, somebody asked Michael Kearney, "How do you see yourself spending the first minute of the new millennium?"
Hint: This Tiptree Award winner features a serial killer protagonist.
34) The five women fell silent as they climbed single file on the narrow woodland track, higher and higher through the long summer twilight, with the soft duff of the forest floor quiet beneath their sandals--or in one case, boot-heels.
Hint: Book 34 starts in Oregon. But not quite our Oregon.
37) (The epigraph which is less obscure than the first sentence.) Four No-Doz and Eight Meg of RAM.
Hint: Book 37 is nonfiction, and a travelogue of sorts, although the author stayed in Florida the whole time she was traveling.
43) Several centuries (or so) ago, in a country whose name doesn't matter, there was a tall, skinny, straggly-bearded old wizard named Prospero, and not the one you are thinking of, either.
Hint: This author is better known for his children's books, but this one is for adults, and features two wizards named Prospero and Roger Bacon, and not the ones you are thinking of, either.
44) Miss Savage was missing.
Hint: Second line: And the French were coming.
Hint: From a series of books that have been made into miniseries on the Beeb.
46) It is his last day, and by six in the morning he is already drinking, drinking and shot up, eyes frantic, limbs flailing like he's ready to explode.
Hint: this book is subtitled "a love song"
51) Under certain circumstances there are few hours in life more agreeable than the hour dedicated to the ceremony known as afternoon tea.
Hint: book was made into a movie with John Gielgud, Shelley Winters, Martin Donovan, Nicole Kidman, Viggo Mortensen, Shelley Duvall, John Malkovich, Mary-Louise Parker, Christian Bale, Barbara Hershey, and Richard E. Grant.
54) September in Pine Cove is a sigh of relief, a nightcap, a long-deserved nap.
55) A big man in brown, sitting behind a table.
56) By the time anyone noticed that the carrier was overdue, no one cared.
Hint: it's from a book co-written by one of the other Elizabeths (that is, not Bear)
57) It was the week following Easter in Reading and no one could remember the last sunny day.
59) Veldt to scrub to fields to farms to these first tumbling houses that rise from the earth.
63) The flotillas of the dead sailed around the world on underwater rivers.
65) There are reasons I hate to drive fast.
66) On the corner of 16th Street and Hieratica a factory sings and sighs.
I added a hint for #51.
List copied from the wiki: http://wiki.shadowunit.org/index.php/First_line_game
ETA no smileys