You are the militia.
We the people, make up the militia.
As for those you see in the media, most are well meaning, Constitutionalists… some are rather absurd in their views, and some are simply seeking trouble…
But, they are not generally the militia spoken of in the Constitution.
Several states (have not done research on all the states to see which ones have militias), have an official militia, aside from the National Guard…
In Virginia the militia;
§ 44-1. Composition of militia. The militia of the Commonwealth of Virginia shall consist of all able-bodied residents of the Commonwealth who are citizens of the United States and all other able-bodied persons resident in the Commonwealth who have declared their intention to become citizens of the United States, who are at least 16 years of age and, except as hereinafter provided, not more than 55 years of age. The militia shall be divided into three classes: the National Guard (Virginia National Guard), which includes the Army National Guard the Air National Guard; the Virginia Defense Force; and the unorganized militia.
The Virginia Defense Force is entirely under the authority of the Governor and not in any way under federal authority. In Virginia it is strictly volunteer. There are also the military schools and cadets that provide officers.
There is a small difference, at least with Virginia, versus our founding era, and that is a well to do person can not simply provide for a force of men and be their commanding officer. During the founding era, while there were fools… most had some knowledge and education and experience with military, tactics, strategy, and warfare, and were capable officers, due to the times, when people studied such, and / or military service in one of several national militaries, British, French, Prussian, Scottish, ……
A small group can form and call themselves a militia, but generally they are not the ones mentioned in the Constitution, with the exception of the unorganized militia which is made up of the citizens of the state, so if you want an official militia, look at your state and see if they have one currently active.