I get emails almost every day from authors, telling me about their books, asking for reviews, etc. And that's fine. I make my email address public and easy to find so that people can always get in touch with me. I like hearing from writers, readers, etc. That's part of why I do this.
Occasionally, though, those emails do more harm than good. Obviously, the crackpots who demand that I review their PublishAmerica masterpiece -- and then just won't let it go -- are among the worst. But sometimes even well-meaning authors say the wrong thing.
For example, I find it irritating when I get a message that reads:
"You should have received a copy of my new book by now. I look forward to reading your review."
Or, even worse:
"I hope you enjoyed reading my book. Please let me know when the review will appear."
I don't know if this is something they teach in management school, or whether some advice guru suggested it or what, but it's annoying.
I am not susceptible to the Jedi Mind Trick. I will not review your book just because you sent it to me. (I get a couple hundred books a month and only review a handful of them.) Most of the time, I can't even read your book. I wish I could. I wish I could read everything and write about most of it. But that's not reality.
Contacting reviewers is fine. Asking if they received the books is fine. (Although you may not get a response.) Anything more than that is probably not a good idea.