What type of forces did Sauron had in the second age?
 

Was it just mordor orcs and goblins? Did he had Easterlings, Haradrim and Variags at his disposal? It's said in the books that during the war with the last alliance, he had orcs, men and other creatures. Does this imply to bats, wargs, fell beast, mumakil, crebain crows, spiders and trolls?

It's pretty much impossible to say what peoples and nations inhabited what parts of Middle-Earth some 4500 years before the War of the Ring, except for Lindon, Eregion, Moria and what very little Tolkien tells us of the Numenorean holdings.

I would think so.

True, but in general I think we can assume that the peoples of the East and South lined up with Sauron.

In some respects we never knew much about the peoples of the East and South so the greater obscurity regarding them in the Second Age is only slight.

Supernatural forces?
 

I've always wondered how Sauron during the S.A managed to destroy the Noldor kingdom by mortal forces. I mean we know how strong the elves were, even more so by high elves. Did Sauron himself contributed his magic to help his forces destroy the elven kingdom or was his forces so massive the elves didn't stand a chance? Or did he had any supernatural forces?

From the unfinished Tales section The History of Galadriel and Celeborn, it looks to me like Sauron simply overwhelmed the Elves with superior numbers.

After all, when the Númenóreans showed up to aid the Elves, it seemingly wasn't all that difficult for them to reverse the tide. If some sort of sorcery had been a big factor in Sauron's early victories, I wouldn't think that should have been the case. And no dragons or Balrogs were around to help Sauron either, it appears.

Ringwraiths
 

If the ringwraiths or similar beings were made by Sauron to lead his armies, would he have any upper hands against Ar-Pharazon and the numenorean army? Or are the numenoreans not so easily scared like their kins in later generations of Gondor?

I don't think Eregion ever had much in the way of population, so I don't think it would be too hard for Sauron to militarily overwhelm it.

Had there been enough time for the Ringwraiths to assume their final form?

Let's say for fantasy sake they assume the form they were in Lord of the rings. Could they drive Ar-Pharazon's army back?

"Drive back?" This isn't the Jacksonverse. The power of the Nazgul is *fear*. Now, anyone who's studied military history, or wargamed, understands how potent a force multiplier that can be: morale is absolutely crucial, and having nine airborne AOE weapons with a -100 Morale attack could be devastating. Tolkien towards the end of Book V describes the effect they have on many of Aragorn's soldiers, even flying high and out of sight.

But then again, as Gandalf told Frodo, "they have no great power against the fearless." Aragorn and Glorfindel weren't deterred, and behind their leadership even the three young hobbits were willing to charge at them. I don't think that Numenoreans at the height of their power would be affected especially badly. (Also: the flying beasts of the War of the Ring were apparently brand-new; anciently the Nine were stuck with horses.)

So it's more likely Ar-Pharazon and his army would stand their ground and try to kill the nazgul? Or would sight of his massive army scare the wraiths away instead?

Yes, Ar-Pharazon's army was the greatest "mortal" army ever assembled, and basically caused Sauron's army to flee in terror. Consider the audacity, even as deluded as Ar-Pharazon eventually became, to invade Valinor. Upon seeing the "Great Armament", the Valar themselves invoked Eru's aid to stop the siege outside the walls of Tirion.

Remember that the Witch-King and the entire army of Angmar were routed by "a small sending-force" of Gondor under Earnur, and that was 2000 years after Ar-Pharazon's day.

He most certainly had the easterlings and Haradrim. As well as hundreds of thousands of orcs, maybe a vampire or two, and trolls.

Bats?
 

Vampires and bats were two different species right? Do you think he had hundred of bats at his disposal and wargs?

I mean the sort of vampires that existed in the silmarillion not the traditional vampires of folklore or popular culture(Tolkien's vampires were quite different from how they were(and are) traditionally portrayed).

He also most certainly had wargs.