Answer:  

Metals do form gases. A familiar example is that there is mercury vapor in fluorescent lamps (mercury is a metal).

However, the properties of solid/liquid metal are very different from that of gas metals. For example, mercury conducts electricity well, but mercury gas does not conduct electricity (i.e. it does not have this property of a metal). If mercury gas did conduct electricity, high voltage could not be applied to the fluorescent lamp making it unable to shine.

In general, metallic elements also have solid, liquid, and gas states. The solid and liquid states are usually “metal”, however, the gas state is “nonmetal”. Since atoms are very close to each other in solid and liquid states, the electron orbitals overlap one another so that electrons are free to move between atoms. Thus, the solid and liquid states have “metallic” properties such as high conductivity of electricity and heat, and brightness. On the other hand, atoms are far from each other in gas state so that there is no overlap of electron orbitals. Electrons cannot move between atoms any more. Thus, the gas state is “nonmetallic”.

Here is a little bit more information about the research at university. As I mentioned above, the transition from metal to nonmetal and the change from liquid to gas usually happens at the same time. It is, however, doubtful near the liquid-gas critical point whether they happen at the same time or not. Landau, famous Soviet physicist, also encountered this problem.
 
 
Acknowledgement
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