Here is the problem and that you bought/ordered them with the Black Friday specials, which in many cases are in (limited) supply, thus many people lose out, since with limited supplies, can't get the specials. Now back in November, can see not concerned, since had not closed on the house thus, the delay on delivery was not a major concern.
But, with a new house and (no) appliances, then odds are that you was buying a refrigerator, stove, microwave and a dishwasher, or even a washer/dryer? But I can see (1) appliance being delayed or on back order, but all of them, then that does not make sense? Or, could it be that they have (some) but are holding off, due to the cost to deliver? In other words, many times if multiple items that are delivered separately, then can bill for (each) delivery?
Forget a lawyer, since YOU will be paying for the legal fees. Home Depot, even with a lawyer will (not) refund/reimburse you the cost of the lawyer.
Is there a Sears store near you? If so, then they have filed bankruptcy, thus maybe able to buy their appliances as a reduced costs, but can only buy (what) they have and there are (no) refunds.
Back in 1995, my (prior) house caught on fire, thus had to replace (every) appliance after being rebuilt. We went to HH Greggs which used to be the best appliance store out there, but is no longer there, since they filed bankruptcy a few years ago. But oddly back then, our house had and we bought all GE appliances and had no problems.
You (might) have to go to another store, like for instance Lowes or Menards as an example and pay more for the same appliances that they (may) have in store, or another brand vs GE. I would not pay more for other appliances at Home Depot, (unless) they are willing to give you a deal and if not, then by going to another store, might be willing or (not).
This is just a suggestion.