What types of antennas are used in a Piper Seneca PA34-200? What types of antenna are used in the Piper Seneca PA34-200 and where are they are located? The manual is not giving the specific answer to the question. Also, what is the frequency range of the antennas?
There can be quite a few antennas:


VHF Comm
VOR
Localizer
Glide slope
DME
ADF
Transponder
Marker beacon
GPS
ELT with integral GPS receiver
ELT
FM Receiver


You can search for antenna at a site like chiefaircraft.com to see what they look like and the frequencies they are designed for. Or go to a manufacturer website, like COMANT Industries, for the same.

Some may have multiple functions in one antenna.

Typical locations: 


Top of fuselage/wing, (VHF comm, GPS)
bottom of fuselage (belly), (transponder, marker beacon, VHF comm)
top of tail, (VOR, glide slope)