Richard is right, it's a real problem
Thank you Richard. It's true. Most free software documentation is obsolete, missing, or just really obscure. IMO it's been *the biggest* impediment to the free software movement. Few programmers enjoy writing. Many of them just don't have the skill, even in their first language. And nobody else has the information to write it for them. It's much more fun to just add features than to write them up. When there's a great reference manual, there's often no tutorial introduction for users unfamiliar with the product, and the product is too complex to pick it up from the reference.
There are exceptions. The manuals for Apache, PostgreSQL, and some of the other flagship products are awesome. Most of the GNU (Free Software Foundation) products are very well documented.
But there are large areas where the documentation just isn't there at all. Sound is still a *mess*, after all this time. The wireless documentation I see the experts sending the newbies to *predates 802.11a/b/g*. Most of the HOWTOs in the Linux Documentation Project are abandoned and obsolete, and you'll do better just developing your skill at composing search patterns for Google. This problem is so bad that the volunteers who answer questions in those famous forums (I'm in debian-users) are overwhelmed and most newbie questions go unanswered.
I've often said a gazillionaire who wants to give free software a push would to best to spend his money hiring technical writers and software quality assurance people to contribute to existing projects, not starting a new distro. Do you hear me Mark Shuttleworth? Where are you Larry Ellison?