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 [...]

This page shows you how to proceed with CallBurner installation from within Skype’s Extras Manager.
1. You should see a “Thanks for downloading CallBurner” page with the CallBurner version number, along with links that allow you to review the available operating environments, and to see other details about CallBurner.
2. Click the “Install” button and follow the instructions [...]

This page shows you how to proceed with CallBurner installation from the first page of the Installer.
1. You should see a “Welcome” page with the CallBurner version number, along with buttons that allow you to review the available operating environments, and to see other details about CallBurner.
2. Click the “Next” button and follow the instructions [...]

Normally when CallBurner runs for the first time, a Skype Permissions window appears to allow you to grant CallBurner permission to connect to the Skype application.
Under some circumstances, however, the Skype Permissions window may not appear. The steps below show you what to do if this occurs.
1. Reboot your PC and start Skype then CallBurner. [...]

To get started with CallBurner, do the following:
1. Check that you have these CallBurner prerequisites.
2. Download CallBurner and install it, or if you have a copy of the CallBurner setup file, open the folder containing it and double-click it.
3. Follow the instructions in the wizard.
4. The CallBurner licensing and startup wizards will be displayed. Follow [...]

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Record Skype Calls:

Record Skype calls to MP3 or other audio formats.
Record incoming and outgoing calls.
Record Skype-to-Skype, SkypeOut, SkypeIn and conference calls.
Record SkypeCasts (both when hosting and listening).
Choose to record just your side or both sides of the call.
Configurable bitrate to trade off quality for file size.
Optionally record calls to [...]

If you have been sent to this page by CallBurner, there has been a problem giving CallBurner permission to connect to Skype. Skype usually asks you to allow access, but sometimes not in an obvious way, and sometimes not at all due to problems in Skype.
Skype 4.0 and later
Skype shows an “Allow access” button [...]

The following software is required to be installed on your system in order for CallBurner to operate correctly:

Skype versions 1.3 to 4.1.
Microsoft Windows 7, Windows Vista, Windows XP or Windows 2000.
(Note: for call recording on Windows 2000, Windows Media Player 9 or later is also required to be installed).

IMPORTANT: You must use a Windows account [...]