Hi all! I have a form on my main page and I want to have the customer fill out a couple of the form items and then based on their selection be sent to the appropriate full form with the 2-3 choices already selected pre-filled out on the subsequent form.

I have seen it done - and I don't think it should be too complicated. Can someone give me a hint as what I should be looking to do to get started?

myabe you are looking for a form that lies on more than one pages(too much long) or there are subsequent questions depended on what user enters first.

in that case you need to submit a part of form ( perhaps you can use ajax ) and then process the user entered input and generate subsequent questions from it.
i suggest, it's better you use Ajax cause it can generate subsequent questions/form fields without causing a page refresh and that looks cool too.

As always. there are many ways to go. You could use ajax as phazorRise suggested, which is often handy. Could be tricky if you're new to ajax though. A simpler javascript solution could be to load the entire form on page but hide (CSS display:none the second part. Then use javascript to unhide it, when the first part is filled.

If you do not want to rely on javascript, the simplest way is probably to submit the first form to another page at which you will recieve the data and analyze it. Determine what the next part of the form should be and output that part. Either with a big if-else-construct or better yet include (with the include() or require() function) a file that has that part of the form.