Creating a Custom Ticket Creation Page

Hi, I need to create a webpage where a user can create a ticket. The
reason for creating a custom page is that the user needs to fill out a
lot of information that doesn’t work as custom fields. (choosing
products, quantities, calculating total price). I just want to make a
normal HTML form that will take the data, then create the ticket,
assigning some data to custom fields and the rest in the body of the
ticket. What’s the best way to do this? Have the webpage send an email
and try to deal with it using scrips when the email arrives, or make a
copy of Create.html where I will add my extra fields (that end up in the
body along with some extra calculations) ? Thanks