You can "pencil test" your preamp tubes for microphonics if that is what you are referring to. Just gently tap your suspect tube with the eraser and if it sings you picked a winner. Yank his butt out and replace him once you have turned off your amp and he has cooled down.
As far as testing your power tubes or even your preamp tubes for life expectancy, emissions, grid leak, and shorts or any other reason goes you can buy a tube tester but you will have to remove your tubes to test them. Tube testing may or may not find a bad tube though depending upon your tester. If you get a tester that does every test or enough testers to accomplish every test then yes you can find the bad tube.
