I don't homeschool, but I do use workbooks with my two girls from Learning Horizons (An American Greetings Company). These are workbooks used by teachers, with answer keys and such. There is a website:
www.learninghorizons.com although I haven't checked it out yet because I just noticed the web address. I can say that both my girls are in preschool and are way ahead of the game according to their preschool teachers. Also, a friend (who teaches third grade) said they had already grasped concepts that some of her third graders are just getting. My girls are three and four years old and can write basic words, basic addition, logical thinking, etc. And these are skills they learned because they enjoy doing the books, not because I pushed them into learning.
Like I said, I don't and won't homeschool them, but I can see a difference between my children and children the same age, even some older and will continue to provide these workbooks and others to my girls.
Bless you for having the courage to homeschool and good luck in your search for information.