SpellingCity.com is a great resource, too.

And if you aren't opposed to tv time, then the LeapFrog Talking Letters, Talking words, etc. videos are really great, too. I know they helped Boo connect the dots re: reading. Racer has seen them too, but mostly he has been learning to read thanks to his sister. Almost daily, she sits down with him in their room with a small white board and goes over letters, letter sounds, words, etc.