For crying out loud... I deployed two Apple Base Stations for over 80 users when our Cisco network crapped out and we couldn't afford a replacement Wireless Controller. Piece of cake, had it in place for 9 months with no problems for over 80 users. Works like a charm, cheap to replace if necessary. Vs crap Linksys.

You've given us very limited to work with. But making a couple of assumptions, you're all on the same site. Here's what I would do, buy a Dell or HP server running Windows SMB 2008 for all your clients, file server and user authentication; I'd get two servers, one a PDC and one as a BDC. I'd go laptop on the Thinkpad end with Windows 7. In house wireless would be easy vs networks and switches, get a couple of Apple BaseStations or go Ruckus Wireless access points (which totally ROCK btw). As far as backups go, clients sync files to PDC, the BDC acts as a backup for files, archives and domain. A couple of local HDD's and maybe one or two stored at a bank for backups, then using something like Mozy pro for offsite file backups. That way you have onsite, near site and offsite-- lots of redundancy. Web hosting, unless you need something fancy like posting something into some local database, be cheap ass and pay the $5 a month for Godaddy. Phones: Go with Phonebooth or use cell phones. Email: Google Apps for your domain. If you're starting from the beginning: Laptops $15,000 - $20,000 Servers and network gear: $10,000 Software: $10,000-$50,000 depending on what you need.