High Speed Wireless 2 computers 2 buildings ?

Hi I have a little dilema, currently living in a remote area running two different Dial Up connections on two computers in neighbouring buildings. The area finally has high speed wireless available after they send their guys to check the on site signal and to install a antenna on the house. One high speed connection is the same price as 2 dial ups anyway but I need to run 2 computers on one connection.

How can I share the connection on 2 seperate computers one being in the house (they set that one up) but I want to have a connection in the garage/music room out back around 30-40 yards away on the same connection ?

Just to clarify I asked the provider about it, they said I can but they won't set it up ?

Is it a simple as pointing another antenna at the one they set up ?

Here are steps to try:

(Be warned this is not a 100% fix)

Try a wireless router , a wireless repeater and two wireless cards!