The scavenger missions in this game are made the more painful by the map markers.  They give you a rough idea as to here the items are.

I have no idea why I am doing every side mission in this game.  What is wrong with me? Must be the fever I have.

EDIT: I wanted a synopsis of the story (since I have not been paying attention to it) so I pulled up a FAQ. It seems I am 4 mandatory missions from the end.

Now that I am level 32 and my Hawk is fully upgraded I am wading through this game, it's awesome.  If ME3 doesn't arrive today I guess I'll go ahead and start the DLC. Not sure.