All CommandFusion devices that are capable of emitting IR signals (including the USB IR Learner) contain an on-board IR Database of over 500,000 IR codes. These codes cover brands across a large array of device types. So in the majority of cases, for standard Audio/Video products such as DVD players, TVs, etc, you won't have to learn any IR codes at all.
Use this page to browse through the supported manufacturers and device types. You can even use this form to generate the exact CFLink protocol command to send.