I've gone through a lot of this myself. Pumping money into social network advertising is not (or highly unlikely) to return a strong ROI but it depends on your product and who you want to reach.
It is much more effective when your brand presence has grown enough to create a Halo around your advertising; right at the start, you are going to burn a lot of cash for little results.
The best thing to do is to get the basics right first. Create multiple touchpoint for your business with social media pages (it looks like you have that). Make sure you have a few videos on YouTube, this counts toward SEO. Be active with blogging and content engagement. Publish on LinkedIn, create a blog and start engaging your audience and drive traffic to your site.
If your business wants B2B advertising, check www.arlians.com; it's in BETA but if you sign up now, you can get some level of advertising access for Free (for life)