The Press Releases Service, like Updates, is quite simple and straightforward.
It has a list view, which shows all the press releases ordered by date and grouped by year, and a detailed view to display each press release (see http://www.wildcalifornia.org/pressreleases/list, and http://www.headwaterspreserve.org/html/pressreleases_list.html for examples).
The fields in the Web Editor for this Service include a Contact Information, Headline, Sub-Headline, Date, and Body field. The Contact Information field contains the text that you want to show up after the "For more information, please contact:" line in the press release. The Sub-Headline field allows you to enter a sub-heading for the press release along with a headline. So for example if your press release read: "Lawsuit Filed to Protect Remnant Klamath Old Growth: Logging Threatens Beaver Creek and Critical Wildlife Habitat" you would enter "Lawsuit Filed to Protect Remnant Klamath Old Growth" as the Headline and "Logging Threatens Beaver Creek and Critical Wildlife Habitat" as the Sub-Headline.
The Press Releases service is connected to Trees Foundation's site, so within an hour after you add a new press release to your site it will automatically be added to the News Center on http://www.treesfoundation.org.