The Home Depot

I have done tens or thousands of dollars worth of business with H/D in the last 10 yrs. But on the 16th of Dec 2014 I ordered a 1000 sq. ft of tile and paid for it after waiting for 3 weeks and traveling 110 miles to get the order I was inform they would NOT honor the price because they made a mistake. WOW false advertising or what and to date have received NO refund how do you do that. The problem was they made a $9,000 mistake hey not my problem I had a contract but they claim they don't have to honor it and they can't find the money ($1000+) but I got a receipt, well seems the receipt is no good, WHAT! My plan after I feel better is to sue as "pro-say" because I can't find a honest attorney. They messed with me for 2 hrs. and finally said they would give me a 10% discount. But where is my money?