So far there are no signal sites or groups regarding exact coin potential analysis, mostly paid news or PR for shillings. You have to research independently.
The altcoins announcements board is now somewhat conducive with honest discussions on the 1st page. You can try to find good altcoins there.
I didnt mean search for signals from others, from some siter, from group, I locking how I can recognize signals for right coins to buy, sell, etc.