Media for Need advice on sharing a network connection.

I have a PC that is connected to a network which gives access to the internet. I wish to share this connection from the PC.

I can't connect anything else to the network apart from the PC itself.

Is it possible to share out the internet connection having the PC that is connected acting as a hub or something?

Ideally, I want to go wireless if possible.

Any ideas would be appreciated.

Thanks.