require affiliate

If an extension already exists for this, please let me know.

I have a site setup where there are consultants that have their own consultant ID. If a customer goes to mysite.com/consultantID, it displays the consultant's information and tracks them through the site (uses a php session).

I'm installing OC and plan to use the affiliate system to track orders back to each consultant. But, each order must have an affiliate associated with it. So, I need OC to be able to grab the info from the session, or if no session is present, reroute the customer to a find a consultant page, so they have to select someone before they can shop.

Anyone interested? Thanks!