Some things to consider. First these wheels will alter the speedometer in a negative way. You will be going much faster than the speedometer indicates. A lot faster which means I hope you like a white caprice with flashes of blue and red. Second this setup will strain your drivetrain, especially the transmission so I hope you keep 2-3000 dollars aside for a rebuild, maybe more. Of course it will probably look cool so do what you think best.
Go to tirerack.com and enter an Impala and 1996 and click on the view with car diplaying the wheel choice. It doesn't list any wheels bigger than 17's for the caprice and 20's for the Impala but it should be the same bolt pattern. You should know that wheels that size are going to give your shocks/springs and especially the brakes, some problems. You should upgrade the brakes if you are commited to 22's. Also, it would look really ridiculous with 22's and tiny little rotors peeking out from the wheels.
If you like the look of the large wheels go to centerlinewheels.com for the wheels. Click on Wheels and catalog. Again you search by car for a list of wheels available. It will be under Chevy/Gmc pickup and Suv-Asstro, caprice. They have sizes from 15's-24's. Centerline wheels are forged and will be much lighter than anything you find on tirerack.com which will help with some of the upgrade problems.