Here's my take on the matter:
I think that "should we be willing to pay" is only a small part of the picture.
My take on this comes, I think, from my background in what I'd call "geek culture", specifically in the corners of Usenet that I hang out, and in a bit of experience with free software of various sorts. That particular culture is heavily centered around the idea of a "gift economy" as opposed to an "exchange economy". It's a nice idea; instead of expecting that everything is paid for, the expectation is that you give people things that they need, and that people give you things that you need. It's a completely impractical way to run an overall goods-and-services economy (except among small groups of people who know each other), as far as I can tell, but for a lot of reasons it works pretty well for information, particularly information that's stored on computers.
I consider newsgroups to be a primary example of this sort of economy; I participate in several of them, answering questions and occasionally asking some of my own. In addition, I benefit notably from "listening in" as other people ask and answer questions that I can learn from. I consider a lot of online websites that have "how-to" information and such to be a similar sort of thing, except not as interactive.
One thing that is quite apparent, I think, is that a thriving gift economy of this sort is a very beneficial environment to be in. If I have a question about an arcane bit of a computer program I use, chances are that I can get an insightful answer within an hour simply for the cost of the effort required in clearly formulating the question. More than that, there are many times where someone else's question gets an answer that's also useful for me; often, hanging around a newsgroup on a particular subject is a very good way to learn a large amount about it, even if one doesn't ask any questions.
Given those realization, I feel that it's important to me to put effort into supporting the gift economies that I find myself in. I write answers to questions in newsgroups not because I expect that I'll get better answers to my own questions as a result, but because I feel that it helps the community thrive. And, similarly, the informational things that I've posted on my website are things that I posted because I wanted to contribute to supporting the cultural idea of "one puts helpful things on websites for free so they can help other people".
So, for me, there's the question of "should I charge money for the things I make available?" That question has a clear "No" answer for me, as a matter of personal choice: I feel that promoting the culture is worth more to me than the money I'd make from it.
On the question of "should I be willing to pay for it?" There are a lot of answers to that.
First, on purely mercenary grounds, if someone else is willing to give me the information for free, there is little incentive for me to pay.
Beyond that: Yes, the information has a measurable financial value to me, but that only implies that I should pay money for it if one assumes that the transaction is taking place within an exchange economy. If the transaction occurs within a gift economy, the fact that the information has measurable financial value to me does not cause me to incur any obligation whatsoever (other than, perhaps, to feel thankful); it's a gift.
Sometimes, I'm involved in transactions that pretty much need to occur in that sort of economy; for instance, software produced by a three-person software company where the programmers are doing this as a full-time job. There really isn't a functional gift economy outside of computer information in existence today, and these programmers need to eat (and ought to eat well, given the quality of their work), so therefore they pretty much need to sell the software for money to be able to produce it. However, when I'm involved in a transaction where it is a reasonable option to operate in a gift economy instead -- and I consider it reasonable to measure this by whether there are people choosing to offer the things in question on that basis -- I prefer to support the gift economy option. Since I consider opt-in gift economies to be valid on all moral, ethical, and reasonable grounds, I see no reason at all why I shouldn't choose to do so.
I do think that, since I am gaining benefit from the general existence of gift economies, I "should" be willing to work to support the existence of those economies by contributing to them. This is not a matter of any form of obligation for the information I've already received; it's simply a sense of self-interest that it increases the likelihood that they will continue to exist and give benefits to me.