ok now I know its bricked

all I hav is the green light
any tips on how not to let this happen again?
I had it working, just in case anyone say follow the tutorial.
is thier any use with my 3 day old slim psp?
what would have to done to fix it? motherboard? how much would it cost to fix?
can I bring it back to the shop under the gareentee?
any advice
