LocalHost: Getting WordPress to work on….

Hi Again – I’m using Ubuntu 11.10 locally and have my WP files downloaded from website and in my www folder for Apache. I’ve dumped the database file from my website and changed all references to http://www.mywebsite.com to localhost/wordpress and the first page loads fine with all the posts there that have accumulated thus far. Trouble is none of the links work. What needs to be changed so that catagories, posts and pages links work?
Thank you.