As Vic said....check the rubber boots on each end of the axle shaft for torn or split rubber. The Outer CV Joint is more apt to have a torn boot. Since these rubber boots are packed with grease they tend to throw out the grease when the boot gets split or torn, so you can simply look for grease stains on the suspension parts and inner fender liner, and perhaps even the inside of the tire.
CV joints rarely go bad, but when they do they will make clicking or clunking noises when turning. This is caused when the boots get torn, leak out all or most of the grease and expose the inner parts of the CV joints to dirt and contamination. If you catch the torn boot early enough, you can simply remove the axle, disassemble the CV joint, clean it, inspect it, and reassemble it with a new boot and fresh grease.
The job is not that difficult but it is very messy. Typically it is harder to get the axles off the vehicle than to rebuild them.
The rebuild kits include new boot with retainer straps and usually the grease too. However, If you check some auto part stores or online stores like Rock Auto, you can often find completely rebuilt axles, ready to install very cheap. Years ago, there used to be a Discount Auto Service Center that would install rebuilt axles for most vehicles for $99 per side including labor.
A cheaper way is to buy 2 piece axle boots, and install them without removing the axles. On some vehicles, the old boot cannot be removed easily without removing the axle. I don't recommend them since installing the 2 piece boots without cleaning, inspection, and fresh grease, the 2 piece boots are not the best choice,... unless you are looking for a cheap fix just to sell the vehicle.
...Rich