People love freebies, especially if they are highly-relevant. Create free, branded content that is easy to access and valuable to potential customers. And then, highlight the offer in your copy - linking the potential customer directly to a landing page with the content… not your homepage. This is an effective tactic to capture email addresses. And further down the line, if they are faced with a problem you can solve, they will be more inclined to contact you rather than the competition.
Example: “Check out our eBook on the best uses if AI.” “A must see guide to SEO.” “Enjoy our free marketing plan template and crush your marketing goals.”