How about a John wallpaper for each month? This is the place to get them. I make them in 4 different sizes (1440x900 | 1280x800 | 1024x768 | 800x600) so click on the link with the size of your desktop :).

JANUARY (click on preview for the size 1024x768px)

800x600 | 1280x800 | 1440x900

FEBRUARY (click for size 1024x768px)

800x600 | 1280x800 | 1440x900

MARCH (click for size 1024x768px)

800x600 | 1280x800 | 1440x900

APRIL (click for size 1024x768px)

800x600 | 1280x800 | 1440x900

MAY (click for size 1024x768px)

800x600 | 1280x800 | 1440x900

JUNE (click for size 1024x768px)

800x600 | 1280x800 | 1440x900

SEPTEMBER (click for size 1024x768px)

800x600 | 1280x800 | 1440x900