Not one person here can answer that question but you. I'd suggest reading the drum tuning bible
Drum Tuning Bible
Once you read through this information you will have a greater understanding of how a drum looks and can match that with what you want to buy.
The real question should be: "What type of wood, what width, what depth...."
Do you see my point.
I prefer smaller toms... my largest is 15" however the next guy might have an 18" as the largest tom.