Here is a site with instructions – I followed some very similar, only needed to set up something like Filezilla afterwards, it was that quick & simple!
<a href=”http://www.microsoft.com/technet/prodtechnol/WindowsServer2003/Library/IIS/31c2427c-c0a5-49fa-9e03-823f34fba3e8.mspx?mfr=true”>FTP Site Setup (IIS 6.0)</a>
When you say “non LAN clients”, you mean the internet ?
If so, the computer will need to be accesible from the internet (i.e. have a public ip address, or be mapped to one).
You could find these articles useful also:
<a href=”http://msdn.microsoft.com/en-us/library/6ws081sa.aspx”>How to: Create and Configure FTP Sites in IIS 6.0</a>
<a href=”http://www.hostmysite.com/support/dedicated/iis/iisftp/”>How do I configure FTP in IIS?</a>
The Windows FileZilla server application can be <a href=”http://filezilla-project.org/”>found here</a>. You will need to open a port on the firewall to permit inbound connections on ports 20 & 21 for FTP. You will