I'm using Django with FastCGI + nginx. Where are the logs (errors) stored in this case?
Errors are stored in the nginx log file. You can specify it in the root of the nginx configuration file:
error_log /var/log/nginx/nginx_error.log warn;
On Mac OS X with Homebrew, the log file was found by default at the following location:
/usr/local/var/log/nginx