On the other hand press releases are an essential tool of marketing! The main aim of a
pr is to announce your site/ product - they should be aimed directly at your target audience/ customers. So they should definitly be newsworthy - not just blah blah new product but - this revolutionary new cleaning product is based on years of careful research etc. You have to compete with a lot of other people doing the same thing!
I would always go direct to the mainstream press or magazines which ever is the most appropritate for your area - ie Estates Gazette for real estate etc. plus the online agencies etc but these carry far less weight. Good luck