The “Downloads/Multimedia” page of the ACLU has a section named “Know Your Rights”. As a non-citizen being living in the US for only 10 months, I’m not really aware of US-specific rights. You can even download and print a pocket card memo.
This was highly informative to me mainly because it validates everything I learnt in american police tv shows. To sum up: find a lawyer asap, keep his phone number with you at all time, call him before telling the police anything.