For trade block, go to strategy, then team needs, then click on a position. it'll show you all available players(FA, Trade, Draft).
For the other two, I'm not sure. I guess the twitter feed? I wish I knew. I just played a season with the colts and resigned Adam Vinitieri, and he retired. I went through the draft and everything and didn't even know he was gone. Same thing happened with Randy Moss. Nothing ever told me they retired. And it wasn't on the front page or twitter feed because bigger players like T. Gonzalez, and A. Gates retired.