There are several ways of getting a Url for a page.  If you want to get a friendly Url from a view, then I would strongly recommend reading this post to see all the options available to you: Creating a friendly URL within your EPiServer 7 MVC View with Route Data.

If, however, you want a quick and easy way in code, then I would recommend using the following approach:

        public string GetFriendlyUrl(string linkUrl, PageReference page = null)
        {
            var url = new EPiServer.UrlBuilder(linkUrl);
            EPiServer.Global.UrlRewriteProvider.ConvertToExternal(url, page, System.Text.UTF8Encoding.UTF8);

            return url.ToString();
        }

You can then call the method like this.  Note, the page link is optional and if you want to you only need to pass in the link url and the API will still give you the friendly URL

var friendlyUrl = GetFriendlyUrl(pageData.LinkURL, page.PageLink);