I like Shiner Bock, I lived in Houston for a while and it was my drink of choice the whole time. But I have been told that Shiner is about as close to a real Bock as Bud is to a real Pils (only with Shiner actually being, you know, good). Passingly similar, but not really the same thing. Is that true? I haven’t seen the other Shiner offerings for sale, but I’ll keep my eyes open.
Spaten I see all the time, but haven’t really tried. I’ll pick some up the next time I am out.
It’s on my list. 
I’ll get there someday, but probably not this year.
My current favorite Shiner is Bohemian Black Lager. That touch of Czech I mentioned…
Crud… totally forgot about bock and dopplebocks!
Anyway, if you want to know about beer styles (any), take a look at this site:
http://www.bjcp.org/2008styles/catdex.php
German beers are in the following categories:
Light Lager: Helles, Dortmunder
German Pilsner: Pilsener
Euro Amber Lager: Oktoberfest
Bock: Bock, Eisbock, Helles Bock, Trad. Bock
Light Hybrid: Kolsch
Amber Hybrid: Alt, Dusseldorf Alt
German Wheat and Rye Beer: Hefe Weizen, Weisse, Dunkelweizen, Weizenbock, Roggenbier
Smoke Flavored/Wood Aged Beer: Rauschbier
A Fresh Oktoberfest batch, a Liter Hier, a Liter dort, of their Festbier prepared especially and presented in a Bier Fair from all of a German gebiet equaling several hundreds of years of Brewer’s/Caskers, is really incomparable. Whose combined experience in bier brewing under the Reinheitsgebot brewing could add up to millenia of beer. Those beers are as special as the finest wine vintages.