riddle - This one is about YOU! (and other things)

This first one is just you plus...
...dwarfs in Snow White,

...bits in a byte,
...tripod's upright,
...and a number that is quite lucky at least in my opinion.

Then there's you plus...
...wonders of yore,
...pawns set for war,
...cat's lives in store,
...and the black ball in a game which has also different colours.

And then, the third one is you plus...
...men's power rings,

...bass guitar's strings,
...insect that stings,
...and one hundred in a system which uses letters to represent numbers.

Finally, you plus...
...time span maternal,
...man's limbs external,
...circles infernal,
...and the smallest card in the deck if you are playing a game where the aces are high.

The final answer is a surname.

Answer

Each stanza refers to

A unicode character. This is clued by the "You" (U) at the beginning of each.

The solutions are as follows:

Stanza 1

7 dwarfs in Snow White
8 bits in a byte

3 legs on a tripod
7 is a lucky number in most of the West

This makes

U+7837, or 砷, which is Arsenic.

Stanza 2

7 wonders of yore (ancient wonders of the world)

8 pawns set for war (on one side of a chess board)
9 cat's lives in store (cats are commonly said to have 9 lives)
8-ball in pool, snooker and similar games

This makes

U+7898, or 碘, which is Iodine.

Stanza 3

9 men's power rings (rings of power from Lord of the Rings)
4 bass guitar's strings
B (or bee) is an insect that stings
C is one hundred in Roman numerals

This makes

U+94BC, or 钼, which is Molybdenum.

Stanza 4

9 months of gestation (time span maternal)
4 limbs on a man
9 circles of hell in Dante's Inferno
2 is the smallest card if aces are high

This makes

U+9492, or 钒, which is Vanadium.

Putting these together, we have

As + I + Mo + V (the symbols for the listed elements)
or ASIMOV, a famous science-fiction author.