Had to share this recipe we tried last night from allrecipes.com - I have never made meatballs before and jumped at the chance to use my crockpot. I haven't eaten spaghetti this quickly in awhile!
Easy Slow Cooker Meatballs
1 1/2 pounds ground beef (skim the grease)
1 1/4 cups Italian seasoned bread crumbs
1/4 cup chopped fresh parsley
2 cloves garlic, minced
1 medium yellow onion, chopped
1 egg, beaten
1 (28 ounce) jar spaghetti sauce
1 (16 ounce) can crushed tomatoes
1 (14.25 ounce) can tomato puree
In a bowl, mix the ground beef, bread crumbs, parsley, garlic, onion, and egg. Shape the mixture into preferred size meatballs. In a slow cooker, mix the spaghetti sauce, crushed tomatoes, and tomato puree. Add the meatballs. Cook on low for 6 to 8 hours.
I used my Oxo cookie scoop to form smaller meatballs and ended up with about 30 of them. The comments on the allrecipes link have a lot more suggestions including browning them in the oven first to harden them up a bit.