what i'm going to do is go to some antique stores or used bookstore and then pick up some "old school" books.. like Curious george, alphabet books - something like that and then rip out some pages and frame them.
or I'm going to trace some figures on the wall of some cute characters - animals or cute people, like Jip & Janneke (see below)
good luck! ;-)
I ordered a lot of the art in our playroom and the kids' rooms from rosenberryrooms.com
If you click on "Canvas Reproductions" there are a ton of choices. Most of them are by Oopsy Daisy or MaryJack Studios.