Kendra found Buffy asleep at Angel home. Episode Whast is my line.

Faint found Buffy in the cemetery when she returned to Sunnydale. Episode Dirty Girls.

And Buffy found the potentials in the tunnel. Episode The and of days.

In conclusion slayers have some ability to track, may be using their intuition.

Yes They Do Have Tracking Ability And Can Track Vampire's But Not Each Other They Just Probably Know What The Other Would Do Or Where They Would Be At Any Given Time That's How They Locate Each Other:-)

Maybe they follow their intuition.