L.K.
Joshua's Potty is a pretty cute one. The video is called Once Upon a Potty. That might be the book's name, too. Anyway, the video does show where pee pee and poo poo come out of, but it is all cartoon style. There is a girl's video and a boy's.
17 months is young to start potty training. A book or two won't hurt, but I think I pushed too much, too early with my oldest. I started around 17 months because I was due to have his little brother when he was 20 months. I had heard of kids being trained at 18 months and thought that sounded great. Well, he didn't think that sounded great. Now he is 3.5 and he would still prefer to poop in a diaper. He only wears diapers for sleeping in, but there have been days that he holds it all day until he gets his diaper on. Anyway, I have given you too much info. All you wanted was a name of a book. Good luck with potty time.