Looking for hardware that works with Windows 7

Microsoft has already published a good article on this:

Looking for hardware that works with Windows 7?

Visit the Windows 7 Compatibility Center to research how to make your existing devices (or devices you plan to buy) compatible with Windows 7.

• Windows 7 Compatibility Center

Having trouble installing a device?

The following resources can help you with device installation problems:

• Installing new hardware: recommended links
• What to do when a device isn't installed properly
• Install, view, and manage your devices and printers

Devices not working properly?

The following resources can help you with devices that aren't working properly:

• Tips for fixing common driver problems
• Update a driver for hardware that isn't working properly
• Automatically get recommended drivers and updates for your hardware