He is in the ring just north of the tent where you get the black knight quests. Facing the tent, look to your right and it's up a little hill.

is there anny cind soul that can uppload a pickture on him.. having really big probs finding the dude :(

NPC located at 68.6,21.00

This is just stupid... after trying numerous different varieties of strats with abiltiy sequences... seems like more stupid luck than anythign else to beat this...

When you turn to the right go up the hill and enter the Argent Valiants Ring... the ring is the farthest west you can go.  Danny is on a box at about 10 o'clock as you face west.

OK, I also don't like to have to play WOW on/as another avitar. I created my hunter because I like to play as my hunter not as a giant or on/in another machine/avitar.  nuf said
If and when you do decide to get on a mount to challenge an oppenent, the avitar menu bar buttons are in order as follows:  #1 Thrust, #2 Shield-Breaker, #3 Charge, #4 Defend, #5 Food/repairs to full health(1 min cooldown) and #6 Duel(instant 10yard range). So after you have chosen an avitar(mount) you would then proceed to press button #4 three times to max it out BEFORE you (enter an arena and) select a challenger to combat with. Then it's a matter of prefference to which button order to use, or combat stategy to employ. Usually it's some thing like TARGET your oppenent first (or he/she will be able to hurt you and you will not be able to do much to him/her) then getting enough distance betwwen yourself and your opponent to use #2 to lower oppenent's defense then #4 to repair your own defense, then get distanse again to use #3 and #1 in rapid succession, and so on, rinse and repeat, to defeat your chosen oppenent.
Different stagegies will need to be practiced and employed to defeat the different levels of opponents thoughout the chain of tourny quests. Good luck - you'll need it.

Awful series of quests.  Proof the Blizzard is losing the ability to keep us entertained. 

Dunno what you people are complaining about, I thought this was an excellent addition to Icecrown, but if your stuck i can give a strategy that works for me. Before you challenge your enemy, press 4 3 times to get it maxed up and take very little damage. Then challenge your opponent. Keep using 1 and when they run away use 3 to hit them, and then twist around and use 2. Now they will be pretty vulnerable so keep using one to do more damage than you did before. If your hit by the enemies charge or shield-breaker (3 and 2)then use 4 to take less damage again. It really is very simple.

Hordesmashin, Level 80 Dwarf Paladin, Draenor Server.

Looking for good tactics for this quest?  That’s a Thottbot problem.  Because the quest is given by multiple quest-givers, depending on your race, the suggestions are scattered all over Thottbot.

The best sequence of suggestions I’ve found are under the quest as given by Marshal Jacob Alerius (the Stormwind Alliance faction) at http://thottbot.com/q13699.  Try looking there.

I am close to giving up on this.  It seems to me that lag has a big part to play i.e. I can hurl my shield breaker, but my opponent has time to turn and race back to start slaughtering me before my charge cool down is up!  Has anyone had this problem and managed to solve it?

Yeah, lag is a real killer on this one.  If you are finding this difficult (and there are a lot of contestants going at it, which seems to increase lag), it's because of lag, as if you're lvl 80 you know what you're doing and this should be a walk in the park.  Leave and try to come back when you can try on your own.  Suddenly you win, where before it seemed impossible.

yeah, lag in Icecrown really blows for doing this, I rarely seem to be able to get a charge off thanks to lag. Be nice if they gave you your own instance to do this in to not have lag issues. Followed advice on this thread and others and still get pwned, so far my best is getting the asshole down to 55% :(
Wish I could face it unmounted with all my DK spells instead of this clunky mounted interface.

Yeah, this sucks.  He rides off, Charge lights up and i fricking break my keyboard pushing 3 and nothing, then he charges and i drop half health, or we're apart, and i press charge and i'm knocked off my horse without him moving.  very annoying.