Extending my wireless network to a second building...need help!

Here is the situation:

I have two buildings.  One is the primary building which contains our fractional T-1 line to the Internet.  This building is both wired and wireless.  We have three Cisco AP-350's which cover the entire primary building with an 802.11b signal.  The second building is about 100-125 ft. from the primary building and is much smaller in size.  I would like to wirelessly (word?) extend my wireless network so that mobile laptop users in the second (smaller) building can access the Internet through our connection in the main building.  Presently, mobile users can get a weak signal (10-20%) right inside the door of the second building but cannot roam through the rest of the second building without losing connection.

We have access to an Linksys WRT54g.  Can anyone recommend the easiest and most efficient way to connect to the primary buildings wireless LAN and then disseminate that signal in the secondary building.

Rough layout??

Primary Building                                                            Secondary Building
LAN------>AP350 )))))))))))Wireless signal))))))))))))))))))Bridge or something----->WRT54g or Something)))))Wireless Sig.))))

Any suggestions would be helpful...including caveats, ballpark price of recommend equipment, or proper configuraiton settings.

This is my first time posting something like this....so I'm not sure how many points to give it.