Hey! It's Ella here. I'm going to share about all the different types of games and toys offered for American Girl Dolls.
From American Girl, sadly, there aren't that many choices. There is the Sleepover Set and the Fun and Games Table, but besides that, there isn't much.
However, do not loose hope! You can actually find stuff for them really easily. For stuffed animals, I would recommend Blue Nose Friends, because they are just the right size. However, any four inch stuffed animal would work. Other things are a bit harder, but you can find them. I'd look at party shops for mini things like frisbees and things, and large bouncy balls are good sized balls. You can also get things on keychains, and cut (or remove) off the chain part, and it should be the right size a lot of the time. Then you can look on Ebay of Amazon for other things.
Hope this helped!