I stayed at the hotel there several years ago: 1 night in a regular room and 1 night in the suite. If you stay, I highly recommend splurging on the suite so you can experience more of the design elements and have a chance to soak them in.
One interesting aspect of the design is that electrical outlets were far more plentiful than was standard at the time of construction in the 1950s, but IIRC Wright had already spec'd those out in the original design from the 1920s. If you stay in the suite you get to experience how convenient this is, convenient even compared to modern construction, rather than simply being told about it during a walk-through tour. (The regular rooms are too small to have many outlets.)
The Arts Center shop also sold a nice range of reproductions, like garden sculptures. You could probably find them (the authentic reproductions) elsewhere, but probably not all together like that; you can't know what to look for if you haven't seen it available.
