For an example of a PR company who make it as easy as it gets, look at Nick Redmayne's Travel Media. They have the PR accounts for major specialist tour operators like Dragoman, Peregrine Adventures, Trek America, Walks Worldwide, Wildlife Worldwide, Naturetrek, Voyages ilena, Encounter, Equine Adventures, Lakes & Mountains Holidays, etc etc.
They regularly send out emailshots to journalists with 'latest news' press releases, but when they do, and it beeps into your intray, Nick himself is live online at his site. You can click on the 'live chat'/'customer support' button on his site and initiate a live chat (messaging).
If you want to follow something up, ask a simple question, or you need pictures or something... how quick and easy is that!