Although a quick search at Apple's site turned up nothing, I couldn't help remembering your questions when I saw the following from
Small Dog today:
QUOTE
Xserve and Xserve RAID "Try Before You Buy" Program: 60 Days Risk-Free!
By Kali, kali@smalldog.com
If you're the owner of a small business (or maybe not-so-small), you may have the need for an Xserve. Many businesses are getting by with setups that are not designed to grow with them; you'd be surprised at how integral (and ultimately cost-effective) an Xserve could be for your company! If you're curious, and you're not sure whether or not this would be the right solution for you, Apple has announced an Xserve "Try Before You Buy" program.
Qualifying customers can order a customized Xserve or select one of our standard configurations. Once the product ships, the evaluation period begins. Should you choose not to continue with a purchase after the 60 Day risk-free evaluation period concludes, you may return the hardware. We would love to talk with you about the Try Before You Buy program; please give us a call at 800-511-MACS for all of the details!
As for whether you need Xserve or could use a less expensive(?) MacPro, you'd need to talk with someone who knows more than I do. However, I'd think what your wanting to do could be done one almost any Mac desktop machine, doesn't sound too taxing to me. However, an Xserve will be much more scalable for the future growth of your company and is designed specifically for the distributed tasks that you want. I think you should contact almost anyone you can find who might be using Xserve/Xserve OS and find out why they are using them.
File Sharing is only part of the process of using a 'server'. Macs and PCs can quite easily 'share' files on an Ethernet network. But you may want to investigate how many people will be wanting to access the same files at the same time. That may be more important than the hardware they will be running on. As you've probably noticed, all newer Macs come with Apache already available, so you could probably set that up right now and 'teach' yourself most of what you might need to know, regardless of what hardware you end up with.
Secondarily, I'd also recommend finding an alternative to AppleWorks. It has not been officially supported or updated by Apple for the past 5+ years. I don't think there is anything in the suite that can't be done better by either Apple or third-party apps which are being actively supported and maintained. There are very few apps that can even read AW files and I doubt the list will grow as the years go by.