This is true of any subject and it is not restricted to the internet, - you do give the right answer when you stated to read the bibliography, the introduction and if possible know something of the author, his "ideology" and where his funding comes from. This is something I routinely do and have for a decade or more. I have found books on the holocaust to be very "problematic" in that they have an agenda, that they typically come with a (preconceived) conclusion and the book is simply a regurgitation of the supporting evidence... there is no objectivity, nor is there even an attempt to "examine" the subject objectively.
Perhaps the best proof of this problem is the near hysteria over any work that contradicts the "popular" line of thought, even the slightest deviation is heretical, and this attitude alone lends suspicion to the authors work. It is reminiscent of the environmental fascists who are so invested in their "research" they threaten any dissent, going so far as to seek laws to criminalize dissent. Some are such zealots, they would make a nazi blush... this is also true among the race and poverty professionals, - professional alarmists, people whose living is tied to the outcome of their "research". I question the legitimacy of any such "research" or the books that come from this type of agenda.
You were right sometime ago, on another thread, where you stated that holocaust is probably the most studied subject of WWII, - I would say the most "over studied" subject of the 20th Century, in itself it has become a faith (actually a paid profession), a faith that competes with Islam and the envirofacsist movement for its extremism and zealotry. - This alone should inspire caution in accepting their conclusions.
** Perhaps the best information on the holocaust is the postwar interrogations and some of the military reports on the subject, they seem less self-serving, - their "livelihood" wasn't tied to their research. I have also found books before the 1980's more "objective" than modern work from "professional" researchers. English authors are generally more objective than American, - though the English authors, like Overy and his ilk (college professors) are ideological lefties, they come from an era where objectivity was honored. Today the government agenda pollutes all research with its "funding" and indoctrination.
Capt14k, Perhaps you have read my Soldbuch threads on this forum, I find lots of information on the interweb but my really detailed information I still get from my books.
Information on the internet can be dangerous, specially on topics about war crimes, holocaust, etc.