I have a 4 year old female German Shepherd that I adopted a year ago. She had to change owners when the original owner had to foreclose on his ranch. She was returned to the breeder and then we got her.

The only way she will accept food is to feed her by hand. We've tried dog food, people food... you name it. She shows no interest in food unless we trick her by hiding a broken up 'treat' that she likes in a handful of food. We've even tried starving her for 3 days on several occasions to make certain she was really hungry. That didn't work. I'm exhausted feeding her everyday by hand. It takes an hour. Any help for this perfectly healthy dog who apparently has abandonment issues? She has a great home here w/ lots of attention, play, exercise etc.

You can't starve a dog, no matter how hard you try, unless in extreme cases where they just can't get to their food. A good grade kibble such as IAMS heated up slightly will always taste good to them. Possibly some boiled chicken mixed in will make it palatable to her. She has obviously picked up some bad habits.

A dog, quite naturally, will eat when he/she is hungry.

Yes, I do agree, hand feeding is not always the best way, but obviosly someone got her used to this.

If she eats the food from your hand then it is not a matter of her objecting to the food.
The simple answer is, just don't do it.
Fix her bowl, offer it to her, give her plenty of time to eat, then take it away.
By continuing to hand feed when she doesn't eat you are only enforcing the undesirable behavior.
I do find withholding food for three days extreme.
How many treats does she eat, is it possible she is just not that hungry because she has been filled up on treats?
I find that in families, everyone wants to give the dog a treat, so you may not realize how many she is getting, ask your family members.

Have you tried an elevated food bowl? Maybe its not because you are hand feeding her, maybe she just doesn't like to eat off the ground.