So how accurate are the illustrations of flies on web sites on the
net? And I guess more important, how accurate are they wne printed
out?

I suppose the answer is, "it depends." But I thought I'd ask anyway.

it depends =)

This is a pretty big issue for me in what I do at work... I'm involved
in long term digital preservation of images and records.

There is a PDF post-press standard for color resolution that is used by
the digital print media to ensure when they depict colors of trademarked
and copyrighted items (cars, hair color, lipsticks, etc.) the colors are
accurately represented, as accurate as what the makes intended them to be.

Unfortunately, as described by others, the devices capturing the colors
(cameras, scanners, etc.) the devices portraying the colors (monitors)
and the devices between the two (video cards, etc.) are not equally
created and basically, you get what you get.

Short of having a Pantone wheel up on the screen and in your hand to
tune the colors of your screen to the wheel, there's no way to determine
how accurate the color representation is.

Larry