passing value from a buttonlist to a field in another form

Hi I'm new here, with little programming knowledge, so please bear with me!
On my website http://www.notulistenvereniging.nl
I have two forms:
1. (Cursusoverzicht): A radio button list with products which can be ordered. Once the user has selected a product and confirmed it the user is directed to a second form
2. (Aanmeldingsgegevens) on which the user enters his personal and address data. On this form I want in the top of the form to display the product and price which the user selected in the first form.

So what I want to do is to pass the chosen product value to a field on the second form. So that the user has a reminder of the product and price he selected when filling in his personal data.

Somehow I can't figure out using the right syntax in the second form to get this working.

Thanks very much for your very swift answer! I had read the tutorial about population, but the terms 'parameters' , 'hooks' etc were unclear to me. But the thread on parameter passing cracked it and I made my form work the way I want to. Thanks very much.
I have a related question though: is it possible to redirect to another form condition on which radiobutton is pressed in another form?