Recently I needed to create a page in WordPress that didn’t have the sidebar on it. Took me a while to find the solution, but the one I found works like a charm. Takes a bit of programming knowledge, but not too bad.
I have put together this post that examines the WordPress template hierarchy and the use of conditional statements. Technically you only need two files for a WordPress theme to work, index.php and style.css.
When searching the Web for free themes outside the WordPress directory, be aware that the popularity, open code, and ease of use in making WordPress themes are attractive to others who can make your web server could become part of a zombie army of machines participating in a DDoS attack on some other website, but some may contain malicious code in there.