What is the best you have found. Anything that will work through plaster and wood lath? Would like to keep under $50.
The best "Stud Finder" that I have ever found is the "Franklin ProSensor 710"
(Interestingly, it does not seem to be affected by "false readings" from power cables etc.)
While I have never had the need to use mine on a "lath and plaster" construction, I would envisage that, if you used it vertically, it would show every lath and in the horizontal direction it would show every stud.
Interestingly, on
http://slickdeals.net/f/7024596-pro...r-at-costco-35-renamed-franklin-prosensor-710 there are "instructions for the "Profinder 5000" which appears to be the same device.
Therein it states: -
"Lath and Plaster
Irregularities in plaster thickness and variations in construction materials can make it difficult to locate studs behind lath and plaster walls. Also, if the plaster has a mesh reinforcement, the stud finder may not be able to detect through the metal mesh. Although many users have success with the ProFinder 5000 on lath and plaster walls, there is no guarantee the ProFinder 5000 will work on all lath and plaster walls."
At $35, you could "give it a try" and let us all know how you go!