Share data with network

I have some devices in our shop that I would like to log certain data to a file on our network. Basically some glorified inventory/process tracking.

About all I can find on wifi application involve sending data to the internet through this "internet of things" which as I understand it is public data. Are there libraries for sending data to a network drive or making stored data on a sd available to a local area network? If so, which wifi devices are supported that are in the more affordable range (not $80 but closer to $15 to $30). Alternately, could data be logged to a google docs spreadsheet (same librarie question).

Alternately, would I be better off connecting a single arduino to our wired network with an ethernet shield and communicating with that device via another wifi device such as xbee. If so, are there libraries that will allow me to share data with our LAN via the ethernet shield?

Run a local web server e.g. WAMP or LAMP which takes the data sent via the Arduino (or other device) in the form of a HTTP GET or POST to the server.

And get the server to update the files on the network.

You could use an old laptop etc as a server or buy a Raspberry PI.