Though I can't be certain, I would highly doubt Toyota would use a font widely available to the public. There are usually "imitation" fonts for popular font designs like Disney (the cursive-looking lettering) but as far as finding the true Prius font, you may be out of luck.
Hybrids: '00 Insight, had an '03 HCH for 41k miles
Re: Prius font style
Here is a website that will get you to some close hits. Depends upon what you are trying to do. Vinyl Plotter? Regular paper graphics? Either way, there are a few fonts here that are very close and if you are familar with some programs out there they can be modified to match the stock Toyota font.
Fonts to vehicle or brand logos is an interesting subject. Most of my experience with fonts is on the Mac, so here is what I can share. My mind is really fuzzy because I haven't talked fonts for a while now.
Apple actually created at least 2 different fonts they have used for product branding and on screen display. Chicago is one of Apple's most famous fonts, and was the default menu display for many years until it was replaced (well really more fonts were offered for menu display) in OS8. Apple also comissioned the font which used to adorn and brand all of their computers until they decided to stop handing out model numbers to their hardware, about the time of the blue and white G3. I'm trying to remember that font name, but it was, and still is, fairly closely guarded at Apple, even though they do not brand their hardware with model names or numbers like they used to .
A manufacturer may choose to have a common font on their vehicles if they are going to use that font for both the brand name on the vehicle and the make. However some manufacturers do not do that. For example, currently Mercury uses the same font for the Mercury brand on their vehicles and for the make and trim grade badging. But Toyota takes a different approach. They have the Toyota logo which is consistant accross their entire line, and they differentiate the text design from make to make. I agree with the others, because they are differing the lettering used from make to make, they are probably not comissioning a full font for each vehicle, but they are probably just having a designer make the logo from scratch.
It has been said: Hybrid drivers come in 3 flavors, greenie, techie and cheapie. Pick any 2.
2005 Prius, Melinium Silver over gray, package 5 (AI)