Ebay Purchased 2407WFP Power switch broken

About a year ago I purchased a new-in-box 2407 off ebay.  Just recently the power switch on the front broke so I have to pull the power plug to turn it off and on.  I'm under the impression that this thing has a three year warranty and I belive it was manufactured in 1/07.  Anyway, I don't have a product service code, order number or any of that business as this was purchased off ebay.  How do I go about getting this thing serviced/RMA'd without that info?  And if I need to do a warranty transfer  where would I do such a thing, etc.  Thanks.