Re: laptop wont start
Clicking would be coming from the hard drive, which would indicate IMO a bad hard drive.
If you've already replaced the power cord (save yourself money next time and test the power cord with a Multimeter prior to assuming the power cord is bad) and you aren't getting power to the system and it isn't booting up AT ALL then you have a bad system board or connector on the system board.
So essentially you have two issues here, the clicking is coming from the hard drive, and if it clicks at startup then it is starting up and trying to read the hard drive. So you could replace the hard drive (probably 40 - 60 bucks) and see if that fixes the issue.
The other issue is the power. If you truely aren't seeing lights and it isn't doing ANYTHING at startup (which you already said it was b/c of the noise, but said it wasn't because of no lights...) it is a power issue which you would need to possibly replace the system board.