The importance of search engines in driving web traffic and promoting awareness and leads continues to grow. Because search engines are (through technology) independent in nature, this is a tailor-made opportunity for PR.
Make no mistake, you need to embrace Search Engine Optimization (SEO), understand how it works, understand how to maximize listings, use Google AdWords, Overture etc..
With that in mind I recommend you take a look at MarketingSherpa’s research report on how B-to-B buyers use search engines. The report is available as a PDF.
“You definitely should adjust the keyword phrases you’re optimizing for and offers you’re advertising to reflect this. Instead of just trial offers or direct orders, promote white paper downloads, canned webinar viewing, tech spec documents, and the killer-app, comparison charts of you versus your competitors (optimized for all their names of course.)”
Murphy's Law 