This choice is really up to you on how much time you have to spend on this. The website and book recommendations in the previous comments are great as is the recommendation of using a Content Management System (CMS) such as Joomla!, Drupal, etc. Another book I would recommend is Web Design and Marketing Solutions for Business Websites ISBN-13: 978-1-59059-839-9 and ISBN-10: 1-59059-839-3. This is a great book which talks about what needs to be in a business website, how to market it, 508 compliance, using CMS software and templates, and many other topics. BTW, don't buy the hype of "IT can't do graphics design and vice versa" as it is usually not true. However, these are not skills you can do well overnight. Just like any other profession, it takes time to get good then great at it.
My end analysis would be to get a good CMS (most are 508 and standards compliant and allow the user to manage their own content and most of the good ones are free) with a good template (which you may or may not have to pay for as a lot of the free templates out there are very nice) or hire out the redesign (because that sounds like what your boss is asking for) to a web design company (keeping in mind that not all DESIGN companies are WEB DESIGN companies although more and more are coming around every day).
Hope this helps.