Disclaimer: Fuck you feds, this is free speech.
You'll first need a VoIP program, I recommend skype, a mic, a voice that sounds manly (Or if you're a woman, you'll get much better results) and the ability to social engineer.
For skype buy the cheapest unlimited calling plan, don't do credits since you'll be doing this a lot if you're dedicated. If you're poor or cheap then use VoIP Discount and just keep making new accounts for free calling.
Look for a store like Wal-mart, Target, GameStop, etc to be your first target. Look at the product you are going to obtain, get the manufacturer's name. Example is WoW - Blizzard or CoD4:MW - Valve.
Here is an example of a script I just made
Hey (nigga), my name is "Name," and I work with "Manufacturer," and we seem to have a problem with "game's," authentication key. May I have your name sir,m'am? Hold on let me just get the info here really quick, yes apparently a bunch of these products are broken (use big words) and we need to correct the problem. Can you please grab the game and read me the barcode? Alright now can you open the game up and read me the authentication code? Its 20-25 characters long. Okay read it to me sir,m'am. Alright now dispose (Or get more keys) of them properly and I'll send more of them and an extra one for inconvience.
Make your own script. Do not use this one, it sucks. To check how long a cd key is just check a serial sites.
This is a good way to make some change or get free games/products.
Also archive this shit. And don't post this on Zoklet, I just don't want them knowing it.
I probably forgot a few things and I'll properly make that shitty script better in the future but I feel like shit right now.