How can I fix my LCD42762HDF Accoustic Solutions TV ?

I have an LCD42762HDF Accoustic Solutions TV that when I switched it on, instead of having a blue light, I had nothing. I then switched it off and on again. Then I saw a small spark where the blue light was normally, and then it went dead.
This was bought about 6 months ago from ARGOS, but I have mislaid the receipt. Can you please help ?