The duel trick, where a mage has to sheep you, doesn't work anymore; I think my way is a good, maybe the only(?!), possibility to go to old ironforge!
Do just what I'm doing in the pictures and it will be very easy for you to get there!
I think its doable with every class, only for the classes warrior, dk, hunter, druid it might be a bit more difficult, because they dont have a soulstone or slow fall effects; but a friendly warlock could give you a soulstone anyway, so its doable with every class!
You need a mammoth for this! The flask I'm using in the pictures isn't nessesary but makes it easier!
And now, let the pictures speak!