and we are taking the refresher in infant care, if for no other reason just to make me feel better! Yes, Goodwill will have dolls or ask friends who have kids!
As far as the dog:
Very interesting that your dog is protective of your belly! They told us in our birth class some dogs do show interesting behaviors, yours is one! Get that on video for later!
And, as PP said, I would not worry about the show you saw where the dogs hurt the doll. I am sure the dogs saw that as a toy, not a child... plus... it's TV, I am SURE they set that up for the camera. Trust me, I work with folks in "reality" TV, there is NOTING real about it, really! They probably teased the dogs first with the doll and they put peanut butter on it to get the shot! No kidding!
So, I really would not add that to your worries! It's like trainers will tell you: Dongs can't tell the difference between some toys so if you don't want the dog chewing on your leather shoes don't give them leather toys, smells the same to them. However, doll to child? Totally different!
Yes, I say go enjoy every experience that will add to this for you, just don't let the classes make you paranoid!