From my experience working for a web design company that also does PR, $1000 certainly won't get you much. A cheap PR firm will charge you at least $100/hour which affords you ten hours. Once meetings, planning and strategics are through, you won't have much left at all. My recommendation would be to learn some basic PR yourself and implement it that way.
I'm guessing by PR you want marketing, and it would be far cheaper and more valuable reading a bit up on it to get a grasp than hiring someone else to do it. Read FastCompany or Inc., they regularly post great articles on that sort of stuff that you can read quickly to learn some valuable base strategies/ideas.
And if you think you don't have time, remember that a PR firm isn't just going to open your website and work magic, they're going to want to spend hours going over your brand, your goals and more. You'll have to have meetings and explain a lot to them. In that time you could easily learn an adequate amount of PR strategies to at least implement something decent.
And I'm guessing if your budget is $1000 you don't need anything major to begin with, which means doing it yourself makes even more sense.
