TRUTH: It's perfectly okay to ask for the sale. The most successful sales people always do ... and that's why they're successful.
One of the most important parts of any sales and marketing campaign is what is called the "call to action;" and you should include it in all your elevator pitches (both written and verbal) as often as you can. Stated simply, a "call to action" is your request to your customer(s) to buy whatever it is that you're selling right now. TODAY!
Sometimes, people do an amazing job of selling others on their products and services, but then they walk away from that customer without officially closing the sale while the opportunity is still hot. If you let them walk away, that opportunity will go cold quickly. Then you'll have to re-sell to them all over again the next time you see them. That's wasted time and energy.
That said, I want to qualify this by saying your "call to action" has to be a lot more savvy than simply sending out an email to a subscriber list that has, for example, a copy of your latest book cover attached and not much else other than, "I've just published this new book! Buy it today!" That will get you very few sales, if any.
For best results, your marketing material (elevator pitch) should answer that customer's known question "what's in it for me? why should I buy this?" in a marketing language they will relate to most, it should include one or two of your top keywords, it should clearly outline the features and benefits of your book, and then it should confidently call your customers to action by appealing to their pain points and providing some sort of immediate solution/incentive to them (e.g. limited time offer, limited supply).
Outwardly asking for the sale doesn't always work immediately. But I can tell you it works a lot better than never asking at all. If you've never done this before, start practicing. Start incorporating it into your elevator pitch so you become more comfortable with it. You'll see an increase in your sales if you do.