Helldivers Terminid Stalker Lair Tracking 

Is what the title says it is.
One thing to mention - Stalker attack patterns have them routinely back off and move in a half circle around your location, meaning that if they've been following you for a while they may attack from a direction that isn't indicative of where their lair actually is. The easiest method to track them is just standing still, and keeping an eye out, because they'll just run straight from the lair to your location.
Also mind that destroying a stalker lair does not instantly kill all stalkers on the field. If a stalker attacks within a couple minutes of you destroying a lair, don't start tracking until the attacks become consistent.