How much CS should you have by any point in the game?
I know my CS scores are VERY lacking. No I don't play ranked. I just play simple normals, but I'd like to get a handle on important stuff like this so I may be able to play ranked and not embarass myself. ( If you happen to look at my profile, yes my ELO is in the ****ter, I know and this is why I'd like to improve.)

200 cs by 20 minutes would be a perfect score, more or less (it's possible to get a bit more but not likely without stealing jungle camps).

The more fighting you do, the less cs you'll have. 150 is probably a more realistic goal to aim for in a typical lane.

Once laning is over your cs matters less, but as long as you swing by lanes to farm them when your team isn't doing anything you'll keep up just fine.

Are you harassing, assisting your jungler and taking dragon? probably 130-150 by 20 minutes.

Have you been in lane for 20 minutes and are winning your lane? 200+

scarra's gotten 300 cs in 24 minutes.

edit: perfect score in 24 minutes is 292, but with wraiths and wolves you can obviously get higer. i'd aim for 100 per 10 minutes, but you CAN get more than that.

What champs do you guys think are the best creep farmers? I like Heimerdinger for mid, Malphite for top, and Teemo for bot.

karth and malz have really easy farms mid, cait bot (easy farm with her range and passive), and vlad/gp top

The gold standard is 10 minions per minute.