You will probably do fine using only free software, such as the ones found on the Free PHP Blogging Software page if you are running a blog.
Running a blog aside, those of you whom plan to handle your site straight from a web browser (without the need for an internet editor) will probably wish a sort of computer software called a information Management System, or “CMS”. Despite its daunting title, a CMS is merely a pc system you install on your own web site itself. It allows you to produce website pages, change its look, and otherwise control your website by just making use of your web browser. There are numerous free CMS scripts (ie programs) around, when you choose this path, you most likely don’t have to purchase such an application (unless you determine to purchase a commercial one alternatively).
Whether you use blogging or CMS software, you will require an FTP client, an application that enables one to move files from your computer to your web host’s computer. Once again, there are numerous free FTP programs available (in addition to commercial people). Obviously, if you are using a free FTP system, it will not run you a cent.