QUOTE(gandalf_grey_pilgrim)
Please at least read before you post. This topic is well documented on the skype website. In windows XP, these files are located at C:Documents and SettingsyourusernameApplication DataSkype , and in linux these files are located at $HOME.skype . They can be backed up simply by archiving these files, and they are cross platform, i.e., you can take the files from windows, copy them to linux, and have your contact list in linux.
You have a small typo error: Linux is "$HOME/.Skype" :-)