I read a comment somewhere about a person reading Lamb right after reading this.  I can certainly understand why, however I must say that Lamb is my all time favorite book, and Good Omens (although excellent) was no where near Lamb. Not even close. Lamb left you a fuzzy yet I've lost a best friend feeling, and Good Omens was just a great story.

Good Omens is a story about Armageddon and the fight between Heaven and Hell, with two angels (one from each side) doing their best to foil the plans. The way they see it, six thousand years wasn't long enough for them. 

Although this book was written by two authors, you certainly would not be able to tell. I will be picking up Neverwhere by Neil Gaiman, and checking out the other books by Terry Pratchett.

Terry Pratchett
Neil Gaiman