Hi Mark!

Just like Jon said it is amp simulator software, and it is definitely still being made by Native Instruments, but now (as you can see if you click the link), they're up to version 5. The biggest competitor is called Amplitube.

Native Instruments (Germany) is one of the biggest music software (and hardware) companies in the world making ALL kinds of products related to music - from great sample libraries and DJ drum pads to products like Guitar Rig, which you can actually get with a physical pedal to facilitate switching sounds.

How are you connecting your guitar to your computer? Usually, people use an external audio interface where you plug your guitar in, and it converts the signal in a good way from analog to digital. This way, the sound you get from Guitar Rig will be a bit better compared to plugging your guitar straight into the computer.

The only problem is that these cost much more than $25...

Let us know how things work out, and we'll try to help if you get stuck.

/Ben