I can't find the location of the spark plugs on my 1997 Isuzu Rodeo LS with a V6 3.2L engine

They are underneath the coil that each cylinder has-you'll see 6 "coils"-three to side-on top of each valve cover. Remove the wire connector from the coil-remove two screws holding each coil to valve cover-carefully pull coil up away from valve cover. If it is stuck-slightly rotate coil back and forth to break it's hold on the spark plug. Use sparkplug socket and long extension to reach sparkplug down inside of valve cover. Driver's side of engine you will find one sparkplug difficult to get because of interference from brake system components. Use TWO short extensions coupled together to reach plug-when it becomes unscrewed from cyl head-lift it up-pull off one extension to clear obstruction-then pull the plug out from valve cover. (I bet you'll see some oil inside the hole where sparkplug was-(sparkplug may be wet with oil-there are seals that keep oil from leaking out of vavle cover). I DID NOT bother to replace the seals-my Rodeo is running just fine with 317,000 miles on her.