I have posted my problem almost on every forum and yet couldn't find someone to help me, usually with no respond at all. I'm using Ubuntu 12.04 with Windows 7 Installed as a Virtual Machine, the only way for me to access the Internet is using a WiMax USB Modem which is not available for Linux, I managed to install it on Windows and get it to work but I don't know how to share that connection with Ubuntu. Could someone shows me an easy way to do that or provide me a step by step guide, I'm no expert so I don't know much about networking, please help me Thanks!
Use a Windows box with the WiMax USB installed on it to act as a router by installing the routing service on it.
Use the IP of this Windows box as the gateway for the rest of your LAN and you are done. I would try to get a WiMax router anyway instead of the USB dongle.