There is a website called statcounter and some things it tracks are...

- where you came from (Country/City/Location in that city)
- your IP address
- where you came from before you hit their site (what site you were at right before)
- how long you viewed the page
- how many times you've visited
- what browser you are using

I used to use this to track visitors to my blog. You can't use it on Facebook, but if you have a blog, then you can put this on and if you choose, it can be INVISIBLE.

If you don't have Linked-in, does your visitor info come up if you search someone who is on the site?