We're in the midst of a long dinosaur obsession in our house. Here are some ideas:
Target has a plastic dinosaur mold set that you can use in the sandbox (we don't have this, can't vouch for it)
Target also has a dinosaur egg with little tools.. you scrape away the egg to "excavate" the dinosaur inside. This makes a big mess, but is fun. It's usually on that endcap that has a bunch of cheap toys in bins.
AC Moore also has several similar dinosaur excavation type stuff.
Imagiplay has a bunch of fun dinosaur puzzles, if you have time to order.
http://imagiplay.com/productswoodenpuzzles.php
Dinosaur books we like are:
Captain Flynn and the Dinosaur Pirates by Giles Andreae
Dinosaurs Galore by Giles Andreae
I Dreamt I was a Dinosaur by Stella Blackstone
Let's Read and Find Out series has several about dinosaurs..
Danny and the Dinosaur by Syd Hoff
Edwina the Dinosaur by Mo Willems
How Do Dinosaurs Go to Sleep (et al) by Jane Yolen
Can I Have a Stegosaurus, Mom? by Lois Grambling
That's all I can think of right now..