1) For a given webpage, do you want to find the last user who accessed the said page?
OR
2) For a given user, do you want to find the last web page the said user accessed.
Then it looks like you need to maintain a table which keeps a track of the pages and the timestamps when they are accessed.
Write a filter (or something similar) that controls the page access and pull user data ( specifically the name of the user) and update the table before displaying the page.