I've heard a lot about using Press Releases for SEO? Is doing this worthwhile? What exactly do you do? Where do you go? Sorry, the idea of using press releases for SEO is new to me.
Press releases have little no impact on SEO. The reason why people recommend using them is every time a website published a press release, assuming your URL is in the press releases, you could get a backlink from their site. What people forget is:
These links are very low value. The pages they are on have no backlinks to them also lack other SEO factors as well, especially if the site publishing the PR is off-topic. So links from them really have very little value. You would need hundreds if not thousands of republished press releases to make these links add up to something worthwhile.
These pages are all duplicate content. Google aggressively rooting out this kind of content so links from these pages may never be found if they are ignored by Google. It's also likely that links from duplicated content like this are also devalued.
So do press releases because you want the press to be aware of something new and/or special on your website, not because you're trying to improve your website's SEO.
PRWeb is a good place to submit press releases. I've had clients do well with them.