Backup software options for small Windows networks
You mentioned that you purchased a USB hard drive to use as your backup media. Centralizing your backup data is a smart way to save money and time.
Your situation exactly describes why we created the Backup for Workgroups product. Over time, we kept running into backup needs that required more more horsepower than personal backup products but we could not cost justify traditional tape-based enterprise backup products.
Backup for Workgroups www.backup-for-workgroups.com can backup all your networked Windows computers and store the backup data to a single, centralized storage device, such as your external USB or FireWire hard drive. It also comes with a mirroring feature so you can mirror all the backup data to another storage device, which if portable can be taken off-site. The smallest configuration is for 3-clients, with quick volume discounts at 5 and 10 clients.