There are many authors nowadays who have come up with their own versions of a Project Management eBook, but just as with any publication, you have to take what they say with a grain of salt. After all, how do you know what the author is saying is genuinely applicable to the field of Project Management?
The first thing you should look for in a Project Management eBook is what Project Management topic it specifically talks about. Project Management is a new field that encompasses many sub-topics so if the author wants to talk about a specific areas (example: Project Management Life Cycle), then you should ask yourself if you really need to learn about that topic yourself.
Next, you should look at who wrote it. If the author is named Bugs Bunny and Company, then obviously you would have your doubts as to whether that Project Management eBook is of value to serious readers. Seriously though, the author is a very important factor to look at when examining an eBook, because you need to know if he/she has the credibility to claim to be an authority on the subject.
Third, try to look for an introductory chapter that will give a brief background of the author. If the author has purely theoretical training in Project Management (having studied in certain prestigious educational institutions) but has very little hands-on experience in actual Project Management situations, you may want to choose someone else as your authority on the subject. Theories have their place, but hands-on experience can never be replaced in value. As they say, experience is the best teacher.
Lastly, you should try to find out when the data being given in the eBook dates from. If the eBook was written back in the 1990s, it may be more prudent to find an eBook thatis of more recent vintage, because of the advances in Project Management that have been made lately.