If you intend to buy a new computer or laptop, it is crucial to buy a Wi-Fi card that is compatible with Linux. Most modern cards will work fine, but it is important to be aware that not all of them are designed to work with free software right off the bat.
Let’s start with the best provider: Think Penguin offers a wide range of Wi-Fi cards that are 100% compatible with free software. Their products include the Wireless-N Mini VPN Router, which has the Respects Your Freedom hardware product certification, and the Penguin Wireless G USB for GNU / Linux adapter, which supports all the major popular and libre (free) distributions.
The entire Think Penguin Wi-Fi line of products can be found here: https://www.thinkpenguin.com/catalog/wireless-networking-gnulinux
Amazon sells many Wi-Fi adapters, and most of them are compatible with the Linux OS. The products that have gotten great reviews include:
1. Panda 300Mbps Wireless N USB Adapter, which is compatible with Mint, Ubuntu, Fedora, openSUSE, CentOS, Lubuntu, Zorin, Kali Linux and even Raspbian Wheezy.
2. Motoraux N300 Dual Band Wireless, which is compatible with Fedora, openSUSE, CentOS, Linux.
3. TP-LINK AC600 High Gain Wireless Dual Band USB Adapter, which includes a larger, and yet replaceable Wi-Fi antenna – a great feature that can’t be found in many other Wi-Fi dongles. So if space isn’t a problem, you can even add an external antenna using a long RP-SMA extension cable to easily gain a +9dB signal boost.
4. Of course, there are alternatives to this solution. If the Wi-Fi signal isn’t powerful in your building, you can use a device similar to the TP-LINK Wireless N300 High Gain USB Adapter. First of all, it runs at speeds of up to 300 MBps. I don’t own this device, so I was unable to verify the claims. Still, most Linux experts agree that the real Wi-Fi speeds can be slightly lower in comparison with the ones that can be achieved by running these devices in Windows-powered environments. I guess that’s the price that need to be paid for using a multi-OS compatible device!