The Tax Book (and probably Quickfinder too) used to have complete examples of preparing returns.  It also has CPE classes; a certain number of hours comes with the subscription.

CPAacademy has numerous free CPE classes (but they are more of an overview than 'nuts & bolts').  At least the ones I've taken. 

You need some basic 'tax prep 101 training' and even some basic accounting training (I'm a firm believer that an understanding of accounting is invaluable when preparing tax returns - even Sch C's that don't require a balance sheet).

In the past, H&R Block offered a class (6 weeks?) that did provided a good, basic understanding.  I sent 4-5 employees to it over the years.  You might see if that's available; I know they changed their process a while ago & want a commitment to work for them, or want a sign covenant not to compete or some such nonsense.