Does the notice say CP2000 up in the top right corner? They send those out when they compare the income on your tax return, to the income that people reported paying to you and they don't match. There should be a list of income sources on one or 2 of the pages included.
♪♫•*¨*•.¸¸♥Lisa♥ ¸¸.•*¨*•♫♪
