Adobe flash player is available via yum. To download flash player, enable adobe yum repo using this command:
rpm -Uvh http://linuxdownload.adobe.com/adobe-release/adobe-release-i386-1.0-1.noarch.rpm
After enabling the repo, install the flash player plugin. Type this command:
yum install flash-plugin
Flash player is now installed in your system, just restart your firefox if is currently running and you can now watch flash content in your browser.