How much are baseball cards worth?

I have over 5 thousand baseball cards and i dont know how much they are worth. I have rickey henderson, mark mcgwire, kirby puckett, cecil fielder, nolan ryan, barry bonds rookie card, tony gwynn, roger clemens, ken griffey jr, cal ripken, bo jackson, pete rose, gary sheffield, eddie murray, bret saberhagen, george brett, ryne sandberg and some i multiples on.