Hello cool guy,
There are several programs out there which can edit the pitch of a wave file, and a few which change your voice while you speak into a mic.
For a pitch editor I recommend GoldWave, which is not free, but the trial version of it has no feature limitation. You can check GoldWave out at:
http://www.goldwave.com/
For a voice changer, a fairly good one is AV Voice Changer 4.0 Diamond Edition, which is also not free; however there is a demo version which you can use, but it has several limitations. To find out more about AV Voice Changer 4.0 Diamond Edition, check it out at:
http://www.audio4fun.com/
Goldwave is easy to use, and I would recommend that you use it, as it also has the ability to perserve the tempo of the wave file, and only change the pitch. Good luck.
- Damon