"She has. Naturally, the ideal location depends on which foes would prove most dangerous to encounter, and how quickly you could deal with these witches. Given that you are from another world, it's hard to be sure what knowledge is lacking, but I'll do my best and will clarfiy any details that are still unknown to you, as best I can.
"The first of the Enemy's soldiery, and the most numerous among them, are the Glamhoth. Glamhoth are shorter than Men or Quendi, and appear ugly to the eye; chiefly green or grey or sallow, but other colors aren't unheard of. They are to the last slaves of the Enemy, and none defy his will or his commands, though they are not without fear. A Glamhoth is typically slower than an adult, and somewhat weaker besides, with worse equipment, but you will almost never encounter them without a group and their weapons are often poisoned with the latest concoctions from the vats of Angband. They lack the grace and keen senses of a Quendi, but are not far from Men on that regard, and often travel with hounds when on hunting parties to flush out their targets. They rarely have any form of armor, but even when mortally they will often still fight. They possess little woodcraft, and their trails and camps can be easily noticed; their coming can be detected, if not from the baying of the hounds, by the flight of birds. They are most dangerous in great numbers or when stiffened by the Enemy's stronger forces, but he seems to posess no real limit on how many he can breed to replace the numbers of his losses, and they can be deadly as distractions or against a distracted force.
"Also among his armies, often in large number, are the Easterlings - men who never escaped from the shadow into the west, and still serve the enemy's purpose. These far more defy generalization, and often cannot be determined as foe on sight, allowing them to pull off sneak attacks. These can and indeed have been swayed back on occasion, particularly with payment of gold or threat, for their loyalty is generally more fickle than that of Glamhoth. The danger of these depends on the group; many of the richer and more skilled groups can be nearly as strong as one of the Edain, but others are less of a threat than even the Glamhoth. More dangerous by far than the normal easterlings, however, are the Gaurhoth - werewolves. They appear merely as Men, but can at will transform into a monstrous form, near as fast as a horse and capable of healing perfectly from lesser injuries; they have great stamina, and are very difficult to outlast in a chase even on horseback. Generally, they don't range far from their master, Gorthaur, but it's not unheard of for the Enemy to deploy them elsewhere. They can act independatly, and have incredibly keen senses, particularly of smell and hearing; they are very difficult to flee from.
"Balrogs are the most dangerous of The Enemy's general soldiery. They are Ainur in their own right, given up their ability to shift forms and utilize their Power directly for an immensely strong physical form and control of flame. Their whips are extremely deadly, capable of shattering poorly made armor or shields in a single blow, and the heat their weapons give off can injure even with a near miss. They don't think like incarnates do, but they are invariably old, clever, and experienced. It's very difficult to disincorporate one without magical weapons, and if you do, they are not slain forever but abandon their body and take their surroundings with them in a massive fireball. There shouldn't be any of these outside of the north, even after the fall of Felagund's fortress at Sirion, for they are not subtle and our forces have not collapsed to that great an extent.
"Glaurung is a type of monster we call a dragon; his breath is nearly as hot as a forge, his scales and claws like steel, and his gaze can hypnotize all but the strongest willed. When he was younger, Lord Fingon managed to best him and drive him back to Angband, but that was nigh on two centuries ago and he proved incredibly fearsome at the battle of sudden flame; even Noldor lines could scarcely stand against him. The poisonous Miasma he trails in his wake can prevent the regrowth of plants for years, and is toxic to Quendi, Men, and Khazad. He is further enormous, and capable of attacking and killing whole groups of soldiers at a time, and it is very difficult to get anywhere with blunt impact. I don't believe we've even reached the limits of his capabilities, either; I would scarcely take him on without an army at my back, and even then I would have to prepare for many among them to end up dead.
"Gorthaur is the greatest of The Enemy's servants, and a Maiar nearly on par with Her Majesty. He is a master of disguise, and of shifting shape, but is also clever beyond any of his peers and possesses a better understanding of incarnates, making him a very effective liar. His power over the song he commands is extremely potent and practiced, and he is a highly accomplished smith. The equipment of his troops far outstrips that of the rest of The Enemy's forces, as often does their quality, such as in his werewolves or the lesser Maia like Thuringwethil that serve under him rather than directly under The Enemy as Balrogs. Do not blindly trust that things are as they appear to be with him; he usually takes the form of a Quendi, but can at the drop of a hat change his shape or cast an illusion over his surroundings to fool the uncautious. Should he venture from his fortress, or you encounter him there by some ill stroke of fortune, I can only suggest you flee."