Getting the Word Out

I am in the process of figuring out how to reach more people when the companies I work with have something to say.  Right now our system is fairly elementary and doesn't make use of too many different channels of communication, but I am looking to change that.

What are some of the best ways to reach more interested people on the internet with news about companies and their recent developments?  How do you reach the bloggers?  How do you drive the traffic without spending the money to buy into something like PRWeb?

I am looking for both advice from you and your individual experience but also links to helpful resources.