Hi,
Found this video off a forum.
I guess you could copy the guy.
What you need is basic riding training and any horse, sit your horse how he is, and every time someone comes near, click the kick combo and kick the bugger off.
He's in Cimmeria on a bridge near a waterfall. Not sure what the co-ords are but Cimmeria has many bridges like it. You can pretty much do it on any bridge to piss people off.
Horses cost 2G, basic riding training costs 1G.
[ame=http://www.youtube.com/watch?v=s-rl3RPC_Mw]YouTube - AoC good times with a horse[/ame]