thanks guys. the tips helped.
-CmR
It helps if you say which specific characters, but here's a short overview:
Fox / Falco: When you throw them off the stage, you have a lot of options. Basic Foxes will jump immediately. Predict it before hand and throw a needle. While they are recovering from that, you can fall down and fair them or hang on the edge and edge guard them from there. When they stop jumping into the needle, you can follow them off the stage and get them while they're firefoxing. Foxes fall into a very specific pattern when they Fox illusion; I can't exactly explain it, primarily because it's 6:21 AM, but you can feel it and simply dsmash them when they get on the stage. If you knocked them well off the stage with a fair or whatever, edge hog, and when they firefox or whatever, jump off the ledge and bair them if they're above you. If they're below you, edge hog them and make them get on the stage, and if you fair right inside the hand of the fair they will go behind you and likely die.
Marth: If he's below you, needle him to disrupt his momentum, then edge hog. Marths always try to sweetspot the ledge because their lag is ridiculous. If he's horizontal to you, depending how far away he is you can needle him, or go down in the middle of his forward b recovery and bair him. You can also interrupt his up b with a nair and trade hits with him, which will kill him.
C Falcon: Whatever you want to do. Needle, dsmash, fair. Edge hog to bair. If they're about to sweet spot the edge and you don't have enough time to edge hog, you can hurry up and run off and bair them before they hit the edge. No character is easier to edge hog than Falcon.
Peach: They love to fake you out and use the umbrella to go for the ledge. They also love to dodge your predicted bair. Just be patient. If they get to a certain point over you where they are obviously going to hit the stage, I ledge hop on the stage and wait for them to land and retaliate. Pretty difficult to edge guard Peach, though.
Sheik: Don't chase her unless you're going to pop her with the bair. Just wait for her to land on the stage, ledge hop on, grab her, and throw her off. I do this all the time because it's very easy to punish her lag. A lot of them will get tricky and up b straight up so they hit the edge when you ledge hop, so wait and make sure they are up bing on the stage -- you have plenty of time.