How can you tell if chocolate is already tempered?
I have some bulk Bernard Callebaut milk chocolate chips.
If it has a shiny/reflective surface and doesn't melt or bloom (much) at room temperature or hand temperature, then it's already tempered. Virtually every packaged chocolate is already tempered.
Untempered chocolate generally needs to be refrigerated for longer-term storage, so if a package doesn't specify refrigeration (and I've never seen one that does), you can assume that it is tempered.
Most chocolate you buy are already tempered(the ones with real cocao butter) but when you melt the chocolate so you can work with it, you must temper it again.
I found this great article on allrecipe in regards to this. It gives step by step information about melting and tempering chocolate.