Help expanding wired/wireless networki

I want to expand my network across two nearby buildings, and am looking for my best options without losing bandwitch.

Build 1 <-------------150 feet-------------> Build 2
<-100ft->
sideA---------sideB C
........................................................................ <-- (network line)

I currently have a wireless g router in Build 1 at side A, which is the side of the house farthest away from point C.
There is a network line that runs all the way across from A to C, but is useless because of the distance.

My current ideas are:
1. Connect two more wired or wireless access points (maybe N) at points B and C?

2. One wired or wireless access point at point B, and a range amplifier at C, or vice versa?

You will need Router N this will give you the range you need and you can get range extender if needed on top of that.

I guess there would'nt be any point in having to N routers, one at point A and B? But I am trying to determine if it would be best to have a wired router/switch at B, and than extend the wire to C, and install another wireless router there.