Chalk Talk: A Kindergarten Blog offers a lot of great ideas including a free 40 page downloadable Dr. Seuss mini unit.
What the Teacher Wants! also offers a free lesson download that includes word searches, self portraits, number sorting, writing, simple crafts and much more.
Oopsey Daisy has a great post summarizing what she did to celebrate several Dr. Seuss books including Green Eggs and Ham; One Fish, Two Fish, Red Fish, Blue Fish; The Foot Book and more. There's even a Dr. Seuss matching game to download!
Finally, check out ObSEUSSed for a lot of great Dr. Seuss resources and fun!
2 Teaching Mommies also has a some great printables and ideas for a Dr. Seuss unit.