Things I Can't Live Without for Spring Rides:

Arm Warmers
Knee Warmers
Defeet sleevless Un-d-shirt(under a regular jersey)
Wind Vest (the wind jackets with zip-off sleeves are great for colder weather).
Smart Wool socks.

If it's really nippy in the morning, I'll also add an earband, "magic gloves" (those .99 cent things you get at the discount store...just pull 'em on over your regular cycling gloves) and plastic baggies over the toes of my socks(inside the shoes...just toss them when it warms up).