Bounce rate is simply the number of users who enter you site at a specific page and then leave without accessing any other pages.
Therefore bounce rate is entirely dependent on your website and what you are offering. Do you want people to visit other pages in the website.
For example, I've just started on a new project (which can be found here: Online Css Minifer) eventually this site will have lots of individual pages, each offering a different tool. Thus I'm expecting a high bounce rate and this isn't really of concern to me.
Do you have any more details about the contents/structure of your website? I know a high bounce rate can look bad but it might not be the end of the world.