Dell 2407 WFP Repair

I have a Dell 2407 WFP monitor that I love.  The power button did the crazy turn thing, but I could live with that.  Now it will power up (as in the power button lights up), but it has no picture.  I tried the self test, nothing.  I tried switching inputs, nothing.  I called Dell service to get a repair/return/replace authorization as it is only about two years old on a three year warranty, but I can't for the life of me find my invoice, so no order number.  I tried to get in contact with the autorized retailer that I bought the unit from, but can not get them to answer my emails. 

So, I was just wondering if there is any recourse for me to follow.  I really love the monitor and obviously don't want to buy a new one if I can get this one covered under warranty.  I bought it on eBay so I can possibly get the winning auction information from them if that would suffice for an order number.

Any help with this would be much appreciated. 

Thank you.