I don't know how much the civic has changed in 9 years, but I imagine its not a huge amount different.

Look on the firewall around the accelerator pedal, find a circular rubber piece and pull it off, there's how you get through.

You'll want to ask Circuit City, Best Buy, a local sound shop as to how to get the radio out, they're all different. but basically what you do, is pull the face off and any trim going around it. Push the keys in, and you're set. If its a stock deck thats in there, then ask a shop.

Door panels on a civic are some of the easiest around. Hopefully this hasn't changed either. Locate any screws you find, on my car, theres a screw behind the handle, in the grab handle, and one real obvious one at the front that can't be seen when the door is closed. Try sliding the grab handle and the door handle to get it out once the screw is removed. Beyond that, the door panel should just pop off with some muscle.

Edit: Window cranks too, if you have them, need to be removed.