I don't have the files, but you need OEMLOGO.BMP and OEMINFO.INF (you will probably have a blank one of these) in your C:\Windows\System directory. If you have access to another Dell, you can just copy them. Or perhaps you can get them from someone else on the board.
Or, you can make your own. Anything you want.
OEMLOGO.BMP can be made with any graphics program and needs to be about 150 x 100.
OEMLOGO.INF can be edited in notepad and needs to have the following lines:
Manufacturer=Dell (or whatever else you want it to say)
Hope this helps,