Lots of sites collect from various sources but make sure to ignore anything to do with the Sun, Daily Mail, Daily Star, Metro, and probably a few others. Sites quote them like gospel but I've never seen any of their rumours come true.
Times, Guardian, Independent seem a bit more reliable and cut out most of the bullshit. I also use Gianluca Di Marzio (mainly Italian with some meh English translated blurbs) which mainly focuses on Serie A but any big rumour from anywhere in Europe usually comes up there before it's a done deal.