Try the "old as dirt" shock test.
1) push down on any corner of the car, enough to push it down a few inches.
2) let go of the car.
3) count the number of times that the side of the car bounces.
4) repeat on the other 3 corners of the car.
5) if anything falls off the car when you do this test, replace it before anyone notices...
If all four corners of the car only one large bounce, your shocks are good! If one or more corners do two large bounces, then its time to get new shocks. If any corners do more than two large bounces, then they should have been replaced thousands of miles/kilometers ago... :P
It's best to replace both of the fronts or the back shocks together, even if only one fails the test.
BTW, if you hear a clicking noise from the rear of the car when you run over a pothole, or a bump in the road, you may have to replace your shock tower mounts. Now, if you hear a screaming noise from the rear of the car when you run over what you thought was a pothole, or a bump in the road, you may have call 911, then your lawyer.

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Shocks, rear shock tower replacements, and coil over kits (for that matter) are available on EBAY.

Make sure your favorite mechanic will install these parts if you don't buy the parts from your mechanic...