ok so my question goes.... My provider (optus, Australia) gives free access to youtube and my space, if i tether the connection to my pc will it still be free?
Tethering
As far as "free" goes...you do pay them for your phone service, so the literal answer is "No".
But if you mean will you entain extra charges....the answer is "Maybe".
The link below discusses the extra charges that Optus has for "tethering" to a PC.
http://www.macworld.com/article/141174/2009/06/iphone_tethering.html
In reality, if you only do it occasionally and your data use is no more than usual with just your phone, they probably will not notice.
In the US, AT&T has been 50/50 with hunting down tetherers who don't pay the extra fee for that service and back-charging them.
When in doubt, read your Terms of Service agreement.