Good news: Though there are many different versions of the Nikon F-mount for use on Nikon cameras over the years, all of them were various incremental changes to add features such as metering, autofocus, electronic control, etc. But the actual mount shape hasn't changed since 1959, so any Nikon lenses since that date would work on a NEX using any of the basic Nikon F to NEX mount adapters.
One thing to remember: On the mirrorless cameras like the NEX, lenses from other mounts are 'dumb' - there's no electronic connection from the lens to the camera, there's no autofocus, and there's no electronic aperture control. That's why it doesn't much matter what version of Nikon lens he has from the past, because all those electronic connection changes won't have any impact when used on the NEX. The only warning is: If his are newer Nikon lenses from the past 10-15 years or so that have removed the aperture ring from around the lens, then you'd have to purchase a special type of adapter that provides an aperture ring on the adapter. This would generally only apply if his camera was newer, such as current Nikon digital camera lenses. If his lenses are older lenses from the film era, especially manually focused lenses, then no worries - the aperture rings are all on the lens, old-school style, and will work fine with the NEX.
The Nikon to NEX adapters are reasonably priced around $25-50 or so...they can go all the way up into the hundreds, but personally I don't find those are necessary. A good, basic Fotodiox, Rainbow Imaging, etc adapter ring will do the job. Good luck!
Sony DSLR-A68 / Sony 18-250mm / Minolta 50mm F1.7 / Tamron 150-600mm / Minolta 300mm F4 APO
Sony A6300 / 18-55mm F3.5-5.6 / 55-210mm F4-6.3 / 10-18mm F4 / 35mm F1.8 / 16mm F2.8 / FE70-200mm F4 G OSS / FE70-300mm F4.5-5.6 G OSS / via manual adapter, lots of Pentax K mount, Konica K/AR mount, and Leica M mount manual lenses