Electronically Coded Keys

[45fan]

A week ago last Friday I purchased a really clean '97 Mustang. The previous owner only had one key, one that I learned later is electronically coded. I called 3 Ford dealerships here in town to learn of how I could acquire a spare key and basically got three different stories, ranging from $25 for the key and $65 for coding to $135 to hook up to a computer for 1 1/2 hours. All 3 stories were quiet different from the section in my owners manual I just read which simply states to turn the switch from on to off with the good key, remove and insert a new electronic key within 15 seconds, turn switch on and programming takes place automatically. Can anyone verify any of the above scenerios? Again, this is for a spare key (as opposed to no key at all) for a 1997. Also, the manual says that the coded keys can be purchased from Ford dealerships or selected retailers. Who would be a "selected retailer"? Thanks for the help!