As a general rule of thumb, the best place to get drivers is from the web-site of the manufacturer of the hardware in question.
Equally, it is not generally necessary to update hardware drivers if the ones you have are working perfectly well. Unlike operating systems and some well known trouble spots like Flash and Java, hardware drivers do not represent a security risk and therefore do not require patching in the same way as, say, Windows.
The time you do need to look for new drivers is if you are upgrading your operating system, for example, from Win 7 to Win 8 (or XP to whatever). It is on these occasions that you may have real difficulty finding drivers to work on your new operating system. Your old drivers MAY work in the new system or may not, in which case you have some hard choices to face if you can't find new ones. I had to bin a perfectly good, and fairly new, sound card when I updated from XP to Win 7 purely because it wasn't supported in Win 7.