I would either get a digital multimeter OR get a Eurotubes bias probe. Not both. If all you're doing is biasing, then you really only need one or the other. If the amp you're biasing doesn't have 1 ohm resistors on the power tube cathodes, then a digital multimeter won't really be useful, considering you're a novice and probably won't want to get into the other methods of biasing. So... that said... get the Eurotubes "Pro One" bias probe. It will show you plate voltage and plate current at the same time. Easy.