wireless connection and transfer using wifi

hi there, here is my idea and I want to implement it, but I'm new in arduino programming
so please tell me it doable or not (:

the goal is transfer images to the server, from a very large distance and no any internet covered

I want to connect serveral arduino devices to wireless network(like ad hoc) and some of devices' job just passing images(cause the distance is too long that one device can't transfer)
for example, there are three arduino devices A, B and C, I want to transfer images from A to C, but the distance is too large, so I connect three devices to an ad hoc network, so A can pass to B then pass to C

so, is it doable? any tutorial to learn? what kind of hard devices should I prepare?

thank you guys so much!

----edit----
I've look for large document and found the WiShield support adhoc (am I correct?)
is there any reference or demonstrate?

Your project is probably easier and cheaper done using WiFi router with an alternative OS on them like dd-wrt (http://www.dd-wrt.com). With these routers you can cover distances with two devices where you would need 10 Arduinos with WiShields just because the antennas are much better.

What distance do you need to cover? What kind of images (size, format) do you want to transfer?

thanks for your reply!
I'll put device on UAV(Unmanned aerial vehicle)so I need small volume, small weight
and the transfer bandwidth need run on 802.11X protocol
and now I just want to try 3 node data transfer, like the example upside
so I want to know, is it doable? and is there any similar demonstrate?

thank you so much !