Editing vpm's is easy, but kinda tedious. There's two user friendly programs for that purpose: Voice Editor v0.8 and Turboccc's NonTTS Voice Editor.
English and Spanish Tutorial for Voice Editor, also with Borat's voice as example:
(of my own creation, made out of speechs and movies - I know it's not as nice as the other voices, but it was my 1st approach heheh -)
And let me point out that these are not TTS files (Text to Speech). Which means, they won't be saying any street names. However, if your GPS does support TTS, you will also be able to upload these .vpms (losing the TTS directions).
If you would like to edit .vpm files with TTS, go to Turbo's website, where you'll find TTSVoiceEditor, an excellent program:
http://audacity.sourceforge.net/?lang=es http://www.dbpoweramp.com/ http://sox.sourceforge.net/
Installation instructions: Download the file, extract, upload the English_American_.vpm file of your choice to your Voice folder in your Garmin device/Storage card (previously make a backup of your original English_American_.vpm).
More voices: SEDARA, PIERRE PISSANT
P.s.: I reuploaded Stewie, apparently fixed now. Pls report.
P.s.2.: Had to update Jill as well... hope she's fixed now. Pls report.
The problem was that some phrases would get cut right at the start or in the middle (e.g.: "searching for..." instead of "searching for satellites").