HTML form generator

[GreenShark]

Hello!
I colaborate in a forum where we are implementing a rule for the used stuff sales.
We have came out with a form that people must fill when posting a thread on what they want to seel. The flling of the form is made by copy/paste and that sucks...
I thought that maybe we could make an html form that would generate a text, based on the fields that people have to fiil, so that it generated an ordenated text so that people would only have to copy it once.
As we have no experts on html programing(though I know the basics) I hope someone here can help us.

Or form(not filled) looks like this:

Tipo de negócio: (radio button to select an option) - mandaroty field
Descrição do produto: (text entered by user) - mandaroty field
Preço: (text entered by user) - mandaroty field
Fotos: (text entered by user) - mandaroty field
Aceito propostas: (radio button to select an option) - mandaroty field
Modo de pagamento: (text entered by user) - opcional field
Outros contactos: (text entered by user) - opcional field
Comentário: (text entered by user) - opcional field

This form would be outside our forum, in an ordinary webpage.
The idea was for people to fill in the form, press a button(or it could be automatic), and it would return an output box of simple text, so that people would copy it to the sale thread.
I think this is quite simple to develop, I just don't have the skills it thakes, can anyone help me out with it?

Thanks everyone,
Luis