As a website or blog operator, there are some basic steps to consider that will reduce your legal risks. One is creating terms of use/service and a privacy policy for your site or blog, which will help you structure your relationship with your users and let them know what your practices are regarding personal information.
The second is taking steps to bring your site within the "safe-harbor" provisions of the Digital Millennium Copyright Act, which can help you avoid liability for linking to other sites containing copyright infringing material and for hosting copyright infringing material posted by your users.