How to set availability for seating on my form?

i need to have something that shows availability for seating for my tours do you have anything that can help me

If I understood you correctly you want to limit availability of seating inside of your form.  

With JotForm you can use the following widgets in order to achieve what you want. 

http://widgets.jotform.com/widget/inventory  

 http://widgets.jotform.com/widget/quantity_gift_registry

http://widgets.jotform.com/widget/gift_registry  

http://widgets.jotform.com/widget/ticket_purchases 

On this thread http://www.jotform.com/answers/519509 my colleague explained in detail how to set Gift Registry widget.

Hope this will help. Let us know if you need further assistance.