1. As others have mentioned, the "winged" things are most likely vibration dampeners.
2. Those "hoops" or oval things are more than likely on lines whose voltage phase to phase is 230KV or higher and linemen typically refer to them as corona rings. At voltages from 230 and up, it is very common for the little electrons to want to jump from any sharp edge or from hardware out into the clear blue sky.(corona discharge) That in itself wouldn't be so bad, except for the fact that when they jump, they take small bits of conductor or hardware with them. This eventually leads to equipment/conductor failure and is very undesirable.
#3
Those "thin wires" at the top of the structure that are above the main conductors are generally called static or sheild wires. They are usually tied to earth ground at every structure and their main purpose is to provide (hopefully) a convenient path to discharge the energy from a lightning strike. I say hopefully because if the lightning hits the static or shield wire and it is effectively grounded, it will not proceed further and strike the phase conductors as well quite possibly causing an outage or line damage.
#4
Handy books to have around are the Linemans and Cablemans Handbook, and "Electrical Essentials" which was written by Wayne VanSoelen and Published By Delmar/Thomson Learning.
A search on Amazon.com in the used book section may line you up with some bargains on either or both of these.
