Tender steaks

You didn't say what type of steak you are using. As someone said below New York and Filet mignon are tender. Also Rib-eye or Spencer is very tender though it has a lot of fat. T-bone is tender, it has the filet and the strip that becomes New York. If you buy Select rather than Choice it won't be as tender.
No one has mentioned cooking temperature. You must cook steak HOT and Fast. If you put it on a cool pan or grill it just gets tougher. Don't over-cook it either. I don't care what the FDA says, if you cook a steak to their standards, it's over done. You don't have to cook it bloody rare but do leave it at least a little pink to keep it from drying out. Good Luck!