For audacity
Here are the steps to begin auto-tuning:
1. Have Audacity, the VST Bridge Plug-in, and Gsnap installed.
http://www.gvst.co.uk/gsnap.htm
http://audacityteam.org/vst/
2. Start Audacity, and make a recording or open up a sound.
3. Go to the effects menu and select the GVST: Gsnap effect. From there you need to set all the settings to the following values:
Min Frequency: 80 Hz
Max Frequency: 2000 Hz
Gate: –80 dB
Speed: 1
Threshold: 100 cents
Amount: 100%
Attack: 1 or 2 ms
Release: 4 ms
Pitch Blend: 0 cents
Vibrato: 0 cents
Vib Speed: 0 cents
Calibrate: 440 Hz
4. Press the OK button and allow Audacity to render the effect. (Tip: For a better sounding effect, go to the effects menu and repeat the effect.)