all those answers are pretty much toast. a CMS is not going to give you search capabilities.
BTW, If you put your site on Google, you can put in your own CSE (Custom Search Engine) through Google Webmaster Tools. saves a lot of code and gives you the list of top 100 keywords people searched on your site so you can optimize.
CSE allows you to put a google search box on your web site that searches your web site only (at first, later searches). if you want to see it in action, go to http://JesusnJim.com
otherwise, you will be writing your own PHP+MYSQL/pgsql code. mysql and pgsql provide different text search functions, but they both commonly have the keyword LIKE, REGEXP.
but to use the full-text search facilities, you will need to alter the structure of your database to FULLTEXT.
note that if you ever decide to switch hosting, you are more likely to find mysql than pgsql, so I suggest learning development in mysql.
the 2nd-last link is the main manual link for the mysql manual.
do NOT do mysql/php development on the production server. install a local web server package li8ke XAMPP or WAMPP on your pc and do development on THAT instead - besides - it's a lot faster. see last link.
use http://w3schools.com for beginner's training on sql, php, and other web technologies. bevvy of stuff.