I would seriously reconsider wireless in your case. The area is drastically developing.

Currently inmac has 802.11g (54Mbps wi-fi compatible) access points for £100. While still more expensive than conventional wires, this is technology which we will be seeing more of everywhere, and by certain the fastest developing technology.

At my house I have a wired setup interconnecting the fixed PCs. This was extremely easy to implement as when the house was being built I could lay the ethernet cables. Additionally I have coverage of access points allowing me to network my laptop. Makes life much easier just plugging in a card and being on the net. I guess for fixed PCs it doesnt matter that much.