I can i build a customiseable form for internet user?

[pendejo]

 

i m trying to find out which method would be the best to create a:

 

web-form.

that the client can build and add field as wanted.

with submit button. (for me to recieve)

with convert to downloadable pdf,txt,doc. (for them to backup)

 

it's for the client to build his Q&A form that could be as long as he want and that i could fill up for him.

 

it seems pretty simple but i can't find anything similar?!@!

 

i was thinking flash..but i find it complicated to mix html and flash...

 

PHP must be a lot simpler but i m not to good at it!!!

 

any help, ex, tut?

 

thanks.