I want to track the source of people filling out a form on my website. Can I set up tracking urls in my banners with something like ...index.php?source=x and then have this source sent with the other variables in my email form? Any idea how to do this?
Depends on whether you want the whole source string in X or whether you want X to be an identifier used to retrieve source information from a database or something similiar.
I want x to simply relate to the source, for example if the person came from an ad in google, then x would simply be 'googleadwords'. The purpose of this, is I want to know which advertising sources are resulting in leads and sales on my site.