Build Wordpress Plugin - Entrance pages for diff sources

Hi, We are looking for a wordpress plugin that will do the following. When a visitor enters our site through the URL [login to view URL] all in-links for the site will append the /1/ so when you go to a post the link will be [login to view URL] or a page would look like [login to view URL] This would be the same for say if a visitor entered through [login to view URL] then all in-links for the site will append the /2/ so when you go to a post the link will be [login to view URL] or a page would look like [login to view URL] However if you go to just the regular [login to view URL] then all in-links for the site will appear normal so when you go to a post the link will be [login to view URL] or a page would look like [login to view URL] We want this to be a wordpress plugin. We want to do this so we can track different revenue streams and different traffic sources. So when a visitor enters and converts 3 pages down in the site we can track them through the url from which source they came. Please ask questions or PM as we will only award the job to someone that fully understands what we are asking for. This job needs to be started right away and we would like to get it done within 1-2 weeks. Thanks