other classes like warriors have defensive stance available eventhough they arent protection or paladins have righteous fury for that.
Mounts and riding skills can be bought in Stormwind. Riding skills in Old Town and the Turtle Mounts on the small island full of Panda's west of Stormwind Castle. It's a small walk from the Dwarven District.
Edit: Oops. I see you're a Horde. Hmm I reckon Orgrimmar then.
and the monk, like the druid or paladin, cannot tank effectively without being in the correct specialisation, that's just the way it is.
2) Riding is a General topic, not a Monk topic. You can find riding trainers near the flight points, or in a stable of sorts.