There are so many tribes in Warcraft that it would take AGES to list them all
With Orcs, I think you're left with a few remnants of Blackrock, Black Tooth Grin, Frostwolf, Burning Blade, Warsong, Stormreaver and Bleeding Hollow (BEST. CLAN. EVER). The Warsong, Burning Blade, some Blackrock and all Frostwolf remnants came together under Thrall. Black Tooth Grin took over the remaining Blackrock and now they lurk around Blackrock Spire. Bleeding Hollow and Stormreaver, to my knowledge, are still renegade
Humans are low on empires as well, but I don't know what they are
Then of corse you have the various tribes of other races, like Tauren, Trolls (All varities), Dwarves (Darkiron, Stormhammer, Khaz'Modan), Elves (High, Blood, Night, Satyr, Naga, etc) and whatever else is there (Centaur, Magnataur, you get the picture)
And the lands? Lordaeron, Azeroth, Quel'Thalas, North and South Kalimdor, Ashenvale, Northend, Icecrown, Khaz'Modan and the Malestrom. Corse they are only the lands we know about
About humans, there's Azeroth to the south of Khaz Modan ruled by king Varian Wrynn, Theramore in Southern Kalimdor ruled by Jaina Proudmore, and I'm guessing there's still some human resistance around the ruins of Dalaran.
As for the different realms in the world, there's Lordaeron, Quel'thalas(both controlled by the Undead), Khaz Modan(Dwarves), Azeroth(Azerothian humans), Northrend(Undead), Ashenvale(Night Elves), the Barrens(not totally controlled by anyone), Durotar(Orcs), Theramore(Jaina's humans), Mulgore(Tauren), The Broken Isles(controlled by no one) and Outland/Draenor(controlled by Illidan, but Kil'jaeden probably has agents there too).
I think these are most of the nations,clans and tribes Thunderlord Clan Laughing Skull Clan Warsong Clan Bonechewer Clan Bleeding Hallow Clan Shadowmoon Clan Shattered Hand Clan White Wolf Clan Alterac Kingdom Khaz'Modan Quel'Thalas Lordaeron Empire Azeroth Kingdom Gilneas Kingdom Dalaran Kingdom The Kul Tirus Stormwind Nation Thunder Bluff Ogrimmar Nation Thaelmore Kingdom Shadow Tooth Tribe Bloodhoof Tribe
Just a few things to say...Quel'thalas wasn't a part of Lordaeron, it was a seperate nation ruled by the Elves, Lordaeron was the northern human nation. Orgrimmar is the capital city of the orcish nation Durotar, not the nations name. And I'm not familiar with the Thaelmore Kingdom...what is that? Did you mean Theramore? Because I didn't see it on there...just wanted to get the facts straight.