How many books do you buy about the topics of your
interest? I have a cupboard full of fishing books.
You see if you are interested in something you will keep buying materials on the subject.
I keep buying internet marketing related books.
Dispite a saturated market.
The point here is that while you can make money from
this market if you are not an expert in it (don't do it). If you have experience in another field (no matter how saturated) do that.
Our friend below had genuine experience in the car industry. He has no competition because no one can write what he is going to write. His information
product is unique and others would buy it based on his
knowledge of the industry.
Then if he was successful he could lay claim to being an expert in the internet marketing field and then write something in that as well.
The biggest problem people face in this business is that they sit back and wait for the perfect opportunity, whereas if you have genuine experience and knowledge in any field then by all means write a book (have a go) no matter how saturated the market.
The amount of experience you will gain from it will be worth heaps in the long run