I think there are two parts to your question:

A) List Building
B) Engagement of your list once built

On the list building side, I would suggest you develop a strong content marketing strategy. With a B2B audience, there are really great affordable solutions like HubSpot that can give you the tools and tracking you need to get a solid ROI on any content you create.

When thinking about content strategy, its rather basic: consider how your business and industry knowledge can be turned into white papers, trade-focused blog posts, downloadable e-Books, webinars, etc. that would offer value and utility to your potential customers. Create that. Then, use SEO, social, and native ad services like Outbrain or Taboola to drive sales lead through that funnel. Make sure the landing pages you create have a strong call to action that includes providing an email. From that point, you can shift to keeping those leads engaged, and driving them through your buyer journey funnel.

Other ways to build your email list can include doing a giveaway when you're at a trade show, doing free webinars that help and ads value to your client decision makers (and require email opt-in). You can also ask related businesses in your industry (non-competing ones) to send emails to their customers (co-branded) inviting them to the resources or webinars you've created. All that to drive traffic to email opt-in windows and build your list.

For the second part, once you have a list, content marketing can play a key role. I assume you know who are the key decision makers on your client's side of the business. Develop content that is valuable and useful to those sales leads, and use email to deliver that content. Again, this is where HubSpot and other tools like theirs can help you outline the strategy and the tactical plan.

I would also highly recommend using services like MailChimp or aWeber to maintain consistent email creative, and to follow email marketing best practices. Their websites are also valuable resources to help you become email marketing JEDI.

Whatever you do, I would highly discourage you from buying any third party lists, and would strongly encourage you to always follow opt-in best practices--even if this is a B2B email campaign. There is no long-term profit in spamming your potential customers.

Hope this helps!

Are you asking which email marketing provider to use? or how to build a campaign? or where to find your target market?

For email marketing providers, there are many options, but for a free service, I'd recommend MailChimp. They are pretty easy to use, but you have to create/send each email campaign manually.

For automated campaigns (drip or sequence campaigns), I use LeadOutcome. They have a very robust service for the price. You can check them out with my affiliate link nickypink.leadoutcome.com

If you are interested in a drip campaign for your services, you can write the emails yourself or hire them out. I know that LeadOutcome has that service, as I'm sure others do or you could hire a copyrighter that specializes in email campaigns.

The hardest part is creating the list. I advise my clients to come up with a really good reason (free sample of the service, free educational guide, subscriber only content) for people to give you their email address and create an opt in. You can then send that offer individually to people you find in your target market. Get into Facebook groups, do searches in LinkedIn, join chamber of commerces or other local business organizations where those potential clients are hanging out. Send them an email introducing yourself and give them your opt in offer along with a link to the sign up form.

Best of luck!

You can take your cue from the business that do advertise. So how do they do it? There are many different marketing campaigns a business can perform, and how a business chooses the type of campaign it carries out is highly dependent on the era and media available in that period of history. Same is the case with the email marketing campaign of yours as well.
Besides if you do have any questions give me a call: https://clarity.fm/joy-brotonath