You won't be able to use Premiere Elements 15 to capture video from tape-based camcorders or players. Adobe removed that feature a couple generations ago.
But you can capture video using iMovie or LifeFlix (available from the App Store) and it will be editable in Premiere Elements.
Good digitizers are also harder to find. Although I see Amazon has some used ADS Pyro AV Links available for about $65. That was long a favorite over at Muvipix.com, although the device has since been discontinued.
You might be able to get away with capturing video with just about any digitizer and it will probably work. FireWire-connected devices are preferred over USB-connected devices -- but, since you're just working with VHS anyway, the results will probably be fine.