Does overhead or underground equip. need UL listing?

Yes.

If you are referring to the insulators, wire & cable, fasteners, poles, reclosers, line switches, etc used by the electric utility to distribute power at medium or high voltages, I must disagree with #1. While some equipment MAY be listed with UL, it is by no means required. UL standards are entirely voluntary, and many types of equipment are not covered by any existing UL standard.

Compliance with UL listing is usually mandated by the local inspection authority or your insurance carrier, incorporating by reference UL standards or the National Electric Code (NFPA 70). In most U.S. jurisdictions the local authority has no jurisdiction over public utilities, which are regulated by the state or federal government. Electric utilities are held to a higher standard, and tend to follow IEEE or ANSI standards rather than UL. For the same reason, the National Electric Code specifically states in its introduction that it does not cover installations under the exclusive control of an electric utility for the purposes of generation, transmission, distribution, metering & control of electrical energy.

One notable exception is the personal protective equipment used by lineworkers. Their safety falls under federal or state OSHA rules, which tend to reference UL standards.