Personally, IMTU oil is relatively uncommon. After all, you need a pretty specific life history on a world to have it. It will be in high demand, though - plastics and fuel. But, there won't be as much available as everyone would like.
Plant material can make up for some of it, but it takes a lot of farmland. IMTU, this means that plastics aren't used in anything near the quantities they are today, mostly being reserved to where they are really needed. Oil isn't needed for all energy production, since fusion reactors can easily provide baseline electrical power. The need for fuel is more for portable, easily stored, high energy density fuel. Aviation fuel is a prime example.
Rare earth elements are another thing traded, as are quality foodstuffs. (or in some cases, just foodstuffs).
The interesting thing is that, over the hundreds or even thousands of years of industrial civilization, most high population planets will have exhausted any economic reserves of even common materials. (on present day Terra, current rates will begin exhausting reserves in the next few centuries, or even decades. Scary.) Even iron ore reserves may only last several centuries for an industrial civilization in the low billions.
IMTU, the need to secure sources of raw materials is one of the major drivers of wars. (along with nationalism and disputed claims to various thrones and territories).
Ore reserves, at least concentrated enough to make mining worthwhile, requires geologic activity, which means larger sized worlds (size 5-6 and up, the higher the better), gas giant moons under tidal stress, or both. IMTU, strip mining with bulldozers, backhoes, dump trucks and dynamite is more efficient then asteroid mining.
This leads all leads to trade, of course.
Interesting note: it might actually be more efficient to ship iron ore through jump to a planet with coal and limestone then to move coal and limestone to a vacuum world, then ship steel out. At least as long as the steel is used to make products on the world the iron ore is shipped to, and then used there, rather then on the planet it's mined on.
But then, no one lives on your vacuum mining world, and lots of people live on that nearby high population planet, and the factories are there, so the ore will be shipped out at first. And since that's the way it started, that's the way the trade patterns, mills, factories and population will develop, and fix that pattern into place for a long time.