is there a plugin that makes a link over the whole wordpress blog so that any time a user clicks they go to a url
I use a plugin called "Page Links To". It's free and you can get it at: wordpress.org/extend/plugins/page-links-to/ It's really simple to use.
I think you should try Wordpress Redirection plugin, it can handle both single and regular expression urls.
Can you create aliases with "Wordpress Redirection", example make a link http:// example . com/item.html have an alias http:// example.com / aliastoitem.html ? I hope I make sense =)