Ampifying my comment about using an existing RTF file as a template.
Create an RTF file prototype of what you want the eventual output to be except for every field that will be filed in by the form data, put the name of the form field surrounded by @ signs (I say @ just for example, any unique punctuation would do)
Now take a look at the RTF file with a programmer's editor (NOT a
word processor) - see where the @ signs show up - this shows you where your form values will have to be plugged in. You will have to read the template and replace the form values -
Java regex might be a good approach if the template is small.