We operate a Clickbank site which is using a clickbank check out link.
We are also joining another affiliate network called paydotcom.
Visitors arrive to site via redirected affiliate links...Clickbank's OR paydotcom's.
We wish to be able to display different checkout links (or completly different .php page) IF the source of the visitor is a [url removed, login to view] affiliate link (like this (which is not our site) [url removed, login to view]
For all other traffic: direct type in traffic and organic Search engine all need to see the current Clickbank checkout link/page. It is only for paydotcom referred visitors where we will need to display a paydotcom check out link /page (only).
We understand there are a couple of ways you one make this happen so in your reply/quote you will need to describe the logic/approach you are planning of using.
We look forward to hearing from you.