Crazy question: what's going on with the old Norton (?) AFB now San Bernardino Intl.? It seems to have a couple of UPS flights a day (compared to the hundreds at Ontario just down the street). Hard to figure out what kind of routes they're flying. And as with most of the abandoned air bases the former rail spurs are gone.

The Victorville base you're talking about is probably George (now So. Calif. Logistics Airport - great name right?). Short truck run from the Victorville yard but afaict there's no team track there so trucks would have to come/go at Barstow. Makes little sense, but there are some warehouses out there. Once upon a time, as with other AFBs, it had a rail spur, but it's long long gone and hard to find any remnants of. KVCV's best known, though, as one of those desert parking lots for inactive (using a polite term) airliners - it's where, among others, Southwest's 737 MAX and Quantas' 747s are parked.

Probably easier to count airports that still have active rail access (usually just a spur for fuel and, at AFBs, weapons delivery) than those that have abandoned it. March's is gone, probably as part of freeway work and/or Metrolink work on the Perris track. Mather's only recently went away, replaced by a bike path using the old rail bridge across 50. Castle still has one, as does Beale, though Google viewing of the tracks suggests that they're seldom used. McClellan has a fairly active set of tracks operated by a switching line, for non-airport purposes (probably one of the few cases where rail-served industrial and warehouse users of former air base land were found, though with little air-side connection). Pretty much none of the naval air or sea bases, current or former, have rail service any more unless they have a major shipyard (like Norfolk or Bremerton).