While looking around the kids section at my local Barnes and Nobel, I ran across BOB Books, which are a learn-to-read program which come in small boxes of however many books to go along with each level. Starting with the Alphabet and working up.
The Alphabet, for example, is 12 books, each about 2 letters. Included is a Parent's Guide with tips and games and activities. The other sets include Pre-Reading Skills, Beginning Readers, Advancing Readers, Word Families, Compound Words, and Long Vowels.
They have other learn to read programs too. I am so excited! They look great and will really flush out our letter curriculum.