For any founder getting started, I highly recommend the book traction: How any startup can achieve explosive growth.

While most of the advice is better suited to well-funded startups a lot of the tactics can be improvised for smaller startups as well.

Another tactic I highly recommend in your emails to prospects is to use personalization. Make sure that your opening has a direct and personal appeal to the customer. In order to look for avenues for personalization look at news about the target company, events and product launches or news aligned in the business segment. I have even seen one industrious sales rep use college football news as part of their personalization tactic.