I'd like to address a few things here.
First of all, the paid service known as "Service Source", is a massive suite of resources for Apple retail sellers and service centers. It includes up-to-the-minute news and updates regarding all aspects of Apple's products, both hardware and software. It includes access to a huge online database of parts, components, software updates, known issues/bugs, testing procedures, internal memos, training resources, and much more, in addition to service and repair information for Apple hardware. My site is not even a fraction of that, and never will be.
Yes, I sell the CDs. That started sometime in 2005, after numerous requests from users with limited Internet access. When you add up the costs of the CD media, the jewel cases, the padded envelopes, the disc labels, PayPal's fees, and the postage, I make a "profit" of about $4 per disc at the $10 price; I _lose_ money on the $5 academic discount price.
This is how it should be, though. Over half of the visitors to this site who have either bought the CD or emailed me with a question have been teachers, acting as de facto IT staff for secondary schools. These are the people who are struggling to maintain LCs and Quadras and Performas in schools that cannot afford $65/hour repair fees, let alone pay the price for _new_ hardware.
I also run Google ads, which are, for ads, pretty unobtrusive and well-targeted. I've bought things from my own advertisers before. Yes, I pocket the profit from the ads. This is one of the ways I am able to supply the aforementioned CDs at low cost, and kick in a little bit for the $100/month server hosting fees as well.
I'm not saying that this site is one big Mother Teresa service event. I use the manuals myself frequently; my initial goal with putting them on the web was to have access to them from clients' businesses and residences (I am a freelance Mac repair technician). I fundamentally think that you should have every right to tinker with the thing you paid for -- the infamous quote comes to mind, "Would you buy a car with the hood welded shut?" And I also derive an entirely selfish pleasure from helping people, especially with something neat like resurrecting an old Mac. I've formed friendships with a handful of people who've contacted me through the site, and that's the best part of this.
I hope that this site continues to be of service to hobbyists, collectors, teachers, DIYers, and the rest of us who routinely get our hands dirty for one reason or another. Thank you for reading.
-- MB