What can I buy to make the internet signal reach farther to the house?

The city provides free internet, but I however am on the outskirts. If I sit outside I can pick it up on my laptop, but I just bought a roku player, I'd like to try out. The signal doesn't reach inside the house. Would the antenna signal booster work? I don't have a phone line either, just a laptop with a wireless adapter. Please help, the cheapest way possible.