I'm curious, do you have any sort of internet connection on your computer, at all?
Assuming your computer is getting internet via a hard line connection of some sort, you have some options.
1.) Look into something called "reverse tethering", its a technique that allows your computer to share its internet connection with your phone (as opposed to the other way around).
2.) If your computer already has Bluetooth or normal Wi-Fi abilities, you can use those to turn your system into a "Wi-Fi hotspot" that you own. Your phone can then use its own Wi-Fi (or Bluetooth, if that's what your computer's using) to connect it and stream as it (and you) please without needing to be right next to it.
3.)Probably the most relatively expensive solution, but you can by a wireless router. Plug your internet cable into the router, then plug the router into your computer, and connect to the router's Wi-Fi with your phone. Want to switch internet providers down the line? No problem, just hook the router to the new setup and it'll still work -- it'll pay for itself down the line.
