LogCat is quite good thing to look at when program goes haywire since it usually shows both system and developer's own log messages.
If you are trying to debug your Android program inside of Eclipse and you cannot see your custom log message, fixing it might be as simple as going to DDMS perspective and selecting your current device (whether real or simulated).
LogCat window displays only messages from device in focus and that might not be device you are currently debugging.