Well the forum should be kicking HIM/HER around if, he/she did, indeed rip you off.
Really, there’s no better place to start than the tutorials forum here on Zbrush Central as well as viewing the excellent tutorials on the Pixologic website and youtube. Once you progress a bit you might find some of the other commercial products very useful and links to those sites are on the Pixologic website as well. I’ve had very good experience with Gnomon, zbrushworkshops.com and Eat3D, but there are some equally great free tutorials if you hunt around for them on the various internet sites. Try to search for Zbrush 4 tutorials so you don’t get confused by earlier versions which do some things slightly differently.
As far as individual training goes, anyone truely qualified to do this is going to have to charge you enormous sums of money to make it worth his or her time. To leverage the time/expense thing one would have to make general dvds or streaming vids offered to the public (unless we’re talking about corporate training of small groups of people costing $$$ that a corporation can afford).
As far as limiting yourself, Zbrush becomes very addictive. Once you get your teeth into it you will probably want to know everything. And what seems complicated to you just now becomes much less so in time. As a beginner I found the terminology scary, but the concepts were easily grasped.
The road is a bit long (as is my post here :lol: ) but it’s a great deal of fun, as is Zbrush Central, itself.
