Quoted:
Can someone give me a detailed explanation of free floating or a link to an article about it? I understand the basics but id like to get a deeper understanding.
How to set up a free floating gun barrel on a rifle

Also, does free floating only matter with a wood stock?
Free floating is generally done with wood stocks but other stocks can benefit also. Basically anything that touches the barrel can affect harmonics and result in an inconsistent gun.

Would free floating be applicable to a .22 or would the impact be too negligable to be of any importance?
I free floaf every rifle I have regardless of caliber. Then I use pressure pads to tweak the consistency of the rifle.