Fisher-Price Little People offers games for preschoolers. http://www.fisher-price.com/fp.aspx?st=2053&e=activities
Starfall allows your child to explore the alphabet. Simply click on the ABCs link to allow your child to practice with phonemic awareness. http://www.starfall.com/
Chateau Meddybemps offers a parent's guide along with online activities for your child. http://www.meddybemps.com/preschool.html