What geophysical instruments should I use to detect water without drilling?
Hydrosource Associates (no personal relation) claims to use the following:


  HSA’s use of geophysical instruments and methods includes seismic, electrical resistivity, ground penetrating radar, electromagnetic, magnetic, gravimetric, self-potential, and magnetotelluric.


Since you're looking for a list, you could investigate each of those technologies above.

However, the one instrument not mentioned above and the most high recommended method is simply using geological maps.