1. Create business catalog (website).
2. Take a cold calls for companies and represent your website.
3. Launch AdWords advertising targeted to the business segment.
4. Launch FaceBook advertising targeted to the business segment.
5. Launch Bing advertising targeted to the business segment.
6. Use remarketing campaigns.
7. Periodically submit new offers and offer them to your customers.
8. Optimize website for localseo.
9. Make website important for seo, for companiews review, grow it for long term.
You can start by few industries. Make a quality job and grow your business.
Do you use some promo items for your business? I would recommend you to think about it too... You can make some Lapel Pins or something like that for this purpose which will work the best for your business. I like using this old-school method and I am happy with the results indeed