My GE Side by Side is making ice inside food packages. Can this be repaired by myself, is it expensive?

This can be caused by a number of things. The refrigerator may be turned too cold. The damper that controls air flow from the freezer to the cold food section may be stuck or frozen or incorrectly adjusted. The air path that is controlled by the damper may be blocked. The defrost timer may be faulty. The thermostat may be faulty.

I'm not sure what to tell you. Are you comfortable opening up the refrigerator and working inside? Do you have a volt-ohm meter and do you know how to use it? Are you comfortable working with electricity?

What kind of packages? Sounds like things got unfrozed, melted out the water and refroze because of a power failure.