Complaint Review: Susan Thomas

I posted an ad on craigslist advertising a book for sale. I resceived an email from a Susan Thomas stating that she was interested in purchasing my book. She stated that she would like to know the final asking price. I told her that the final asking price was fifty dollars. She stated that she would send a money order first class from San Antonio to my address and then arrange for pickup of the book. I gave her my address. The money order came in the mail with a name of Fred Thomas and the address was 141 Lavaca San Antonio, TX 78210. I got suspicious. The address when googled belongs to an educational district in San Antonio. I examined the money order by holding the evelope up to the light. The money order says it is from Albertsons. When checking moneygram's website, I found that there was no moneygram outlet in an Albertsons in San Antonio. I received an email from Susan Thomas. She stated that her husband accidentally sent the wrong amount on the money order. MY book was only fifty dollars and the money order was made out for 985.00. She asked that I cash the money order and then reurn the excess amount to her authorized shipper. She stated that I could deduct funds from the amount in the amount of 30.00 for gas expenses to do so. I contacted her by email asking for her home address. She responded with "Kindly confirm that you received the money order." I stated that I was turning it over to the authorities, and unless she provides me with a legitamate address, I was going to shred it. I have recieved no reply since.