I bought a car from a neighbor, a 93 honda civic. He said that his son needed to charge the battery, and connected the charger to the battery - without disconnecting the battery. So the voltage went throughout the whole car. He said that since then the car will not start. It is a really nice car. Before I send it to the mechanic I figured I wouls at least change the coil. But where is the ignition coil located?

Inside the distributor.

Thank you - I removed the distributor cap but cannot remove the protective plastic housing around the ignition coil because the rotor will not spin. I cannot get at the lock nut to remove rotor. The battery is fully charged, but when the key is turned in the ignition, there is nothing - no clicking, no lights on dash, horn will not work, no ecm codes. Just dead.

I checked all the fuses, they are OK

Don't worry about the coil at this point. It sounds like your ignition switch is bad. You want to check it out. Your focus, at this point, must be to get the CEL to come on for 2 seconds and then go out. You also want to hear the fuel pump run during this period. So check out the ignition switch, under-dash and under-hood fuses, and main relay. Make sure to use a test light or multimeter to test all fuses. Particularly focus on the ACG (S) ALT 15 A under-dash fuse.

Read Sections A and B in the link below:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-honda-civics-46563.html