OOBOX iTuner can help you to tune your instrument--by ear. OOBOX Tuner will play one sound for each string, you just have to reproduce the same sound on your instrument. Using the digital tuner your computer can record the sound of your guitar (with a microphone or a direct cable), OOBOX iTuner can show you graphically the distance between the good note and the note you are playing.
||Free to try
||Windows 98/Me/2000/XP, sound card