powers on but doesn't boot

@bobyau this "and all i hear is clicking every few seconds" leads me to believe that this is a bad HDD. I suggest that you start off by putting your iPod into diagnostics mode. Use something like this video or look through this threat and follow those instructions, Let us know what results your diagnostic give you.

This iPod is actually easy to work on and it is reliable with an outstanding sound quality. It is definitely worth any repair. Here are all the guides you'll need to work on it iPod 5th Generation (Video)