My 4 year old nephew loves Tom and Jerry and has asked for a T&J cake for his 5th b-day. I would like to do the cake shown on the Debbie Brown Cartoon Cakes book. My question is . . . for Tom's head, can the sports ball pan be used or is that too small?

I have that book, and I went to look at the pictures for you and it said that a bowl shaped cake is used to make Tom's head. Where the cake has risen, trim away the crust slightly, leaving a flat area for the base of Tom's head but still keep a rounded edge slice two layers into the cake and sandwich back together with buttercream I know this is long but I was trying to give you as Much details as possible I think you can use the ball pan, because when you use the buttercream you will get the height that you want
HTH

I don't have that book but I know which cake you're talking about. All of DB's cakes are tiny so I wouldn't have thought the ball pan would be too small at all.