While I might not speak for all authors on this, if you spot a spelling error, typo, etc, in one of my books, then feel free to tell me. In fact, I welcome it. Some readers of mine have stated in the past that they did not want to offend me by pointing out errors, but I just want to state that that is poppycock. It takes effort to inform me of typos, I know, so I in no way expect it, but I also know that some people enjoy spotting keyboard farts, and it is to those people I now speak.
In my early days, I could not afford nor risk large sums of money on editing services, so I paid hobbyist editors who were either looking for experience or enjoyed helping authors out for a bit of pocket money. These people helped my books reach an 'okay' state. My more recent books like Soft Target and the Picture Frame have been edited by professionals (I'm talking editors who charge over a thousand dollars per book). I have no problem paying full price for an editor, as I want my books to be as close to perfect as I can make them.
However, even using a top-class editor, typos and odd errors still make it into the final draft. When my editor sends me changes, I retool and rewrite things, and in doing so, I often leave more typos in the final draft that gets published. It is really frustrating, and getting rid of every tiny error sometimes feels like an impossible task. So, if you are reading one of my books and spot an error, feel free to tell me (if you want to). I will be very grateful and will make the correction immediately. As an Indie writer, I do not have the luxury of an eighteen-month production schedule per book that includes a dozen editing passes. I just have you guys. :-)
So snipe away, if you feel so inclined. I won't take it personally.
FYI: It can be a pain to point out errors on a Kindle reading device, but you can let me know about typos by quoting the erroneous word along with the the word before and after it. For example:
"The cate sat on the mat."
Just send me: "The cate sat" and I will be able to search and find the error in my manuscript.