Rent your own Teamspeak server now at 4Netplayers.com
If you have activated file transfer in your tariff, you can upload data to your server.
This is done via the TS3 client.
To do this, simply right-click on a channel and select "Open File Browser".
A new window will open. In this window you can then simply right-click and "Upload files" to upload them to the Teamspeak 3 server.