Recently found a project that is an emulator for the Cisco 7200 router! It has a Linux and Windows port, and just requires you to have an IOS image for the 7200 series for you to start playing with Cisco commands on your own PC. This is NOT a simulator, so it's feature set will be as limited as the feature set of your IOS version. This software is still in development, so your 7200 image may not boot, but apparently most do. Check it out here!
P.S. If you have a 7200 router in production at work, you should be able to download the image from flash:
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