Brand new refrigerator, but evaporator fan blade broken, causing considerable vibration and noise.

Really, really, really easy:
1.Unplug refrigerator (electrical safety).
2.Remove cardboard cover at bottom of refrigerator (two short self-tapping bolts) with a wrench.
3.Pull old fan blade off fan motor shaft (just held on by a compression fitting--no tools needed).
4.Push new fan blade on shaft.
5. Replace cardboard cover.
6. Plug in refrigerator, write nasty letter to Frigidaire.