have searched a lot but did not find a plugin or tool which can do what I'm looking for:
A user has an account with a ref ID like domain.com/ref=123
The User has filled out a custom field in the backend like: "Your XY-ID is: 4567"
We have a subpage like domain.com/subpage where an outgoing link like thirdparty.com is beeing displayed.
Now the tricky part:
When someone comes through the ref-link like domain.com/subpage/ref=123 The outgoing link should be an individual link from the referral und should look like thirdparty.com/ref=4567
Does that make sense?
I have two examples:
To whatever site on this domain I add my ID, the links on those site have also my IDs attached: http://www.empowernetwork.com/company-blog/?id=3tsd
simple2advertise.com is exactly that: I login, put several IDs in custom fields and it generates squeeze-pages wich point to my autoresponder and so on. Like this page: http://simple2advertise.com/c/?u=3tsd&c=dreams