Brian, I've used TaPoR for a few of my classes to offer data mining (http://portal.tapor.ca/portal/portal) capabilities to, say, Heart of Darkness. We looked cursorily at the recurring use of elephant, tusk, ivory in the novel and were surprised to find that none of these are really prominently used, especially considering that the entire novel is based on the commodification of a living thing.
You might also think about using JUXTA to compare multiple version -- similar to a Hinman Collator (http://www.juxtasoftware.org/). MONK is another good one, but I haven't used it in class yet so I can't attest to its pedagogical efficacy (http://gautam.lis.illinois.edu/monkmiddleware/public/index.html). TokenX is another great one for visualization (http://jetson.unl.edu:8080/cocoon/tokenx/index.html?file=../xml/base.xml).
Ok, in terms of readings about textual studies/scholarship, I find that undergraduates fair better when I just explain it to them. If they want to move further into textual scholarship, I have references for them. But reading the big, heavy stuff can be a bit daunting. McGann, Greetham (Textual Scholarship), Tanselle, etc, are the big guns. Might I suggest a book that's geared towards undergraduates and beginning graduate students? Erick Keleman's Textual Editing & Criticism: An Introduction is mighty fine for your purposes (http://www.amazon.com/Textual-Editing-Criticism-Erick-Kelemen/dp/0393929426).
You might also take a look at my reading schedule for a Materials & Methods grad course that I taught a few years ago; some of the articles might be meaty enough for your purposes but not more than mouthful: http://www.sjsu.edu/faculty/harris/ResearchMethods/Methods_Intro.htm#sch
It sounds like what you want to do is build a scholarly edition and then add in some scholarly assessments. We've been fighting a bit about this in the textual realms -- if a crowd-sourced digital edition is the way to go. Ray Siemens, et al. have been working on a format for this (dynamic social edition). You might read through these two articles for help:
Bertrand Gervais, "Is There a Text on this Screen?" A Companion to Digital Literary Studies
Ken Price, "Electronic Scholarly Editions," A Companion to Digital Literary Studies
Then you might see these about using tools:
The Babbage Engine
"Where Computer Science and Cultural Studies Collide," Matthew Kirschenbaum
"Literature to Infinity," Inside Higher Ed, Scott McLemee
"Algorithmic Criticism," A Companion to Digital Literary Studies
, Stephen Ramsay
"Quantitative Analysis and Literary Studies," A Companion to Digital Literary Studies, David Hoover
"Literary Alzheimer’s," New York Times Magazine
(These last two categories of suggestions are all available online & in my reading schedule for my DH Honors course from last Fall, 9/21 & 9/28: http://www.sjsu.edu/faculty/harris/DigLit_F10/Schedule.htm
Two students and I are currently grappling with how to represent a Modernist artist's renderings of some Wilde poetry. We will probably go with Omeka, but we're intending to have this peer reviewed and live on our library servers as a piece of scholarship. (We'd also love to have the page turner plug-in from the Internet Archive but that might be a pipe dream with Omeka.)
Bethany, Neil, Ray, Kirstyn, Whitney, Matt K., Steve R., et al might have better/more suggestions too.
Lots of primers on how to create a scholarly edition exist, but I haven't found a really great introduction to building a digital scholarly edition just yet. Please let me know if you do! and please share with us your finalized syllabus.