Robert Sabuda's website
Seriously, this guy is one of the leading producers of pop-up books. Some of them have SO many pop-ups that you literally can't close the book once you've opened up all the little doors and niches and so on. One of my favorites is still the Cookie Count
Sabuda also has pop-up cards. I bought the whole set of his Christmas Alphabet cards, as well as two different styles of plain Christmas cards.
Sabuda sometimes collaborates with Matthew Reinhart, who also has a website
. He's at least partially responsible for the Star Wars pop-up book, which includes glowing lightsabers and other cool stuff.
Another good pop-up artist is Jan Pienkowski
. Her books are much simpler than Reinhart and Sabuda, but the art is bold and in my opinion much better for smaller children.
Two other books of some note are by David A. Carter: One Red Dot
, and Blue 2
. I don't like these as much, since the art is all rather abstract, but there is a red dot or a blue 2 on each page of their respective books, so that gives the kids something to look for. (A couple are well enough hidden that you really have to search for them.)
One of my favorite pop-up books ever is Francesca Crespi's The Nativity
, which has six scenes. Two or three of them start out flat but open out to form small stages when you pull (gently) on the sides. The rest are traditional pop-up pages, but some have wheels that can be turned or tabs to pull to reveal more details.
Another is The Wide-Mouthed Frog
, which is a terrific read-aloud book. The pop-ups are comparatively simple, but the art grabs the attention, and kids ask to have it read several times.
Sorry for going on at length, but I collect pop-up books, and did a presentation on them at my local Barnes and Noble a couple of years back.