I have tried this on this server. Unfortunately it is extremely difficult to get people to be willing do give you a shot. That I believe is the biggest hurdle. If you die, they will all want a 'real' tank, even if a warrior would have died just as fast, which has been my experience when I've healed. 
 
	As to talents, you are really selling yourself short by skipping healing. You wear low armor gear. You have no tanking cool down and no mitigation buttons except for healing spells. I believe that the original intent for shaman tanks was for them to heal themselves.
 
	Your threat can be very good even completely untalented, especially at low levels, just by using earth shock and rock-biter as is. Your rotation will be pretty boring too, just auto attacking and earth shocking.
 
	I would recommend something along these lines:
 
	http://db.vanillagaming.org/?talent#hZVcb0xxzZVf0x0xo
 
	You would approach this by first spending 15 points in restoration, at least. This will provide you with the mitigation you need by making healing while tanking more feasible through healing focus, a shorter reincarnation cool down for when you need it, and a process to buff your armor when you criticize heal, which will be often.
 
	From there, you could either get to nature's swiftness, which will leave you with two short CD tanking could downs in reincarnation and NS, and will give you a head start on your heals criting with tidal mastery for the armor bonus, or you can go into enhance and get to parry (the 6-10 talent points are up to you, I like Imp gw). I personally would got the 21 in restoration before heading into enhance and I will explain. All of the tanking potential you get from enhance boils down to about 15% avoidance at most and 10% armor. Avoidance is completely random and out of your control. The armor increase is nice, but it will be nicer at higher levels when you have mail. The healing talents provide you mitigation that is under your control for the most part, and are useful early on. Plus you get cool downs for durability.
 
	The last 9 points could go lots of places, but this is the core tanking spec imo.
 
	For stats, you want Stam>Int/crit for more mana heals and AH procs>Agi
 
	You are a hybrid class. Embrace it.