If you have a mac you can use garageband as an amplifier for any electric guitar. Its easy to set up and you can get really amazing tones with the built in presets and customizing features.
adapter from 1/4 guitar cable to 1/8 audio in or usb to guitar cable adapter
Step1
Plug your guitar cable into the guitar and plug the other end into the adapter you choose. I recommend a 1/4 to 1/8 adapter. This works great on my imac. You can then plug the adapter into the audio input on the back of the computer.
Step2
Start up garageband on the computer. If it is not on your dock it will be in the applications folder of the mac hard drive. Make sure your guitar volume is turned down and you do not hit the strings when you turn on garageband. For some reason it will cause a delay in your play sometimes.
Step3
In garageband go to new track and then select real instrument. A timeline will open with a list of preset guitar tones to the right. Turn up the volume on your guitar and the computer, choose a tone that you like and rock out like you have a real amp.
Tips & Warnings
play around with the many tones and settings available.
try recording yourself and then play it back to see how you sound.