How I can find customers? - (Mar/28/2013 )

Our company sells switching power supply and I'm new to this industry. Been five months I've tried sending develop letters for many potential companies through their public website mail but got no response. We already have stable customers but under the pressure for presenting at least one customer in six months which is close to the deadline. I'd like to know how can I do better to get the target if anyone can advise me. It is much appreciated for any of your comments.

Thank you and best regards,

Who are your potential customers: companies or labs? Sending letters may not be enough to lure customers, door-to-door sales may work better.

@pcrman
Thank you for your response. The thing is our company doesn't do door to do, we do business with overseas customers and we don't do exhibition too. So the only resource I can use is from internet. I've uploaded our products on B2B webiste too, but don't get frequent inquiries. I'm just wondering how to find out a company's key person to contact with, since i haven't got response from companies I sent mail to their public website and I realised it's not working well. Really appreciate your time replying me

How about using social interactive networks such as Facebook, Google,Yahoo, Linkedin, Netlog etc,etc. Good luck..