You kidding me? You can still get High Fidelity tube amplifiers, Audio Research makes 'em, a friend of mine has an Audio Research tube preamplifier, model SP-6c, and a digital amp Audio Research model D-40 tied together, sweet stereo, albeit power hungry. The digital amp is more power hungry due to it's insane power supply, you can look up the details. The company is still around to this day. They are not extremely powerful, if you want power, you're best bet is a newer digital amp at the cost of sound quality or a pair of really good amplified speakers, or, a really powerful amp hooked to the preamp outputs. I myself have a golden piece of the early digital era, a Pioneer SA-8800 made in 1979. It needs some work and I need to get a good pair of mackie studio monitors for it, but it is absolutely awesome.
Oh, and for the record, you CAN still buy tubes. They are made in, wait for it... Not China... Not Taiwan... Not the US of A... Nope, none of those... They are made in Russia, because, in Russia, many people who are poor still use ancient soviet tube technology.
