Photoshop Elements 8 Pre-Installed asking for Serial Number

I just bought a Dell Studio 1558 laptop.  It came with pre-installed software including Photoshop Elements 8.  I installed Shockwave, Reader, Flash and AIR today from Adobe's website.  Now when I launch PSE 8 and click to launch Edit  it asks for a serial number or to start a trail period.   When I click on Organize, the PSE 8 organizer launches fine.  I contacted Adobe and they said I need to provide them my Adobe serial number.  The software was pre-installed, so I do not have any serial number and no CD's or DVD's were provided by Dell for any software with this computer;.  They did not even provide recovery CD's.  I had to create my own. 

Anyone else experience this issue or know how I am supposed to find the serial number?