We've mentioned spring desktop wallpapers recently, but of course there's much more you can do for spring than just change your wallpaper.
One of my favorite skins to use for spring is from don5318 called Simple Green. This is a nice WindowBlinds skin that has an overall minimal design, but with beautiful touches of spring colors sprinkled in.
Not specifically designed for spring, but Reality by LightStar has a perfect color scheme that matches well with a bunch of spring and nature themed wallpapers.
There's no shortage of spring animated wallpapers for DeskScapes, but one you should definitely check out is Spring Falls from AzDude which has a beautiful waterfall scene.