SkypeIn is a ordindary phone number which people call and the call is routed through to Skype where you pick up the call.  Skype offer differnet SkypeIn numbers for over 20 countries with different area codes for each.  Skype offer SkypeIn as the following:

a 3 month subscription where you pay in advance to keep your [...]

Follow these steps to record calls made from an ordinary phone (landlines and cell phones) to your SkypeIn number. These steps assume you have Skype and CallBurner installed. Do you need help with installing CallBurner, or perhaps installing Skype?
1. You will need to purchase a SkypeIn number if you don’t already have one.  [...]