While many of our brethren have successfully coexisted with Macs for years, most IT departments are just now seeing a critical mass. Its ok to feel afraid, frustrated, or hesitant. We were all there once and we'll get through this together.
Hardware:
Notebooks: MacBook, MacBook Pro and MacBook Air. Most folks will use the MacBook or MacBook Pro. $1000 - $1500ish. The hw specs should be extremely familiar. Treat it like a Dell or HP. 4GB of RAM, hard drive is bigger than it needs to be, and the processor is almost certainly up to any task.
Desktops: The Mac Mini is a low cost ($600) box that can get you started. Available in a 2GB or 4GB model. You can easily add your own peripherals (standard video, kb and mouse ports) and avoid the Apple markup. The iMac is the beauty that your marketing department is demanding. It includes a monitor and bluetooth keyboard/mouse. Its performance specs outpace the Mac Mini. At the high end, what a PC manufactuer would call a Workstation, is the Mac Pro. It can swing 2 Quad Core processors and up to 32 GB or RAM.
Backup: All Mac OS X systems come with a backup utility called Time Machine. This is a complete imaging utility (similar to Acronis) that can backup the OS, configuration, and data to a USB hard drive or other media.
Anti-Virus: Symantec, Trend Micro and McAfee offer agents for their enterprise products that support OS X.
Printing: Drivers exist for many, but not all printers. Expect to hassle with this issue. See the full list of supported printers here: http://support.apple.com/kb/HT3669
Warranty: Each Mac comes with 90 days of phone tech support and a 1 year hardware warranty. It is strongly recommended you add AppleCare to bring those to 3 Year terms. Apple does not offer an onsite warranty plan. Everything is a depot-type warranty.
In the next post we'll take on integration with Active Directory, Group Policy, and network drives.