There are a couple of options for installing Skype on Centos 5.5
Dynamic means to dynamically link to libraries, and will require you to meet the dependencies of skype, while static is a larger package which meets those requirements. I went with static.
First, make a directory to download the code to (you can use /tmp if you want):
(alternatively: wget http://www.skype.com/go/getskype-linux-beta-dynamic )
#upack the download
tar jxvf skype_static-18.104.22.168.tar.bz2
cp skype /usr/bin/skype
cp -r avatars/* /usr/share/skype/
cp -r lang/* /usr/share/skype/
cp -r sounds/* /usr/share/skype/
And your skype should be up and running!