Custom Htaccess File

Seeking a freelancer to review and rebuild our htaccess file. We are running Joomla 1.5.23 and have been seeing a lot of duplicate content as well as non-existing URL combinations in our Webmasters. This has been going on for over a year and many think that it is an incorrectly configured htaccess file. A summary of current problems: My initial problem was with 'Not Found' and 'Unreachable' URL's which were a combination of good links and odd variables such as [login to view URL], category-table, section-blog and [login to view URL] These links would ultimately end up looking like [login to view URL] when the correct link is simply [login to view URL] Now I know the first question will be in regards to SEF URL's and having them configured correctly. So yes, I do use apache and I did rename the htaccess file long ago and the site works just fine from the front end. I also do not use any plugins or components related to 404s or redirection aside from the component "Redirect" which appears to be the safest one. I previously used RedDJ and a few others but deleted them long ago. I am also starting to see duplicate content show up in HTML Suggestions, the duplicate content is either a product of the link format discussed below (the real link and a weird variation of it) but also bad links based on the article id. For example, let's say article id 62 is "widgets" I am finding bad links with the id 62 in them and duplicate meta information but completely unrelated to the widgets content. The rebuilt file would hopefully fix these problems by accomplish the following: 1) Redirect non-www URLs to our www version 2) Eliminate duplicate content found by robots (if possible). 3) Eliminate/remove content with [login to view URL] in it. Apache is turned on and our website has no visible links with [login to view URL] in them, however robots keep finding them.