These days, even the least expensive PC will be more than capable of running all the general business-admin tasks that you may need to do for your practice.

The big retailers
The big retailers like, PC World , offer some great 'PC Packages' which are extremely hard to argue with. Buying from a local store also gives you some assurance that when problems occur - you don't have to travel too far to moan on a face-to-face basis.
You will also probably save money on the cost of the operating system - (it's cheaper if you buy it with the PC) - and may get other useful equipment (like a printer or scanner) bundled into the deal.

Building your own
If you already have some experience, own some working PC parts or can't find a package to suit, you may be able to build a better PC Package at less cost:

1. Read-up about the latest offerings on the PC market.
2. Buy all the bits online - at dabs.com or ebuyer.com
3. Build it yourself - adding software to taste.

Remember - on top of the hardware, you will need to pay for an operating system (e.g software like Microsoft Windows) and some other software, like Microsoft Office, which will make your PC useful. So, if you are comparing prices of a 'self-built PC' to a retailers 'PC Package Deal' - make sure you compare like-with-like.

Networking:
If you want to connect two or more computers in order to share your patient information then you need to have one computer acting as a server, with either Windows XP or Windows Server as its operating system in order to ensure that database files are shared properly.