I've recently gotten into a project with, admittedly, little prior knowledge.  I am using a TinyDuino and a Tiny Shield accelerometer. Am I correct in thinking that with the two effectively plugging into one another, I have no need to wire the accelerometer into the protoboard?  I'm following a wiring diagram that was made for another set of hardware (Arduino Pro Mini & MPU6050 accelerometer) but I'm trying to make it work with my current TinyDuino pieces.

Am I correct in thinking that I don't need to physically wire to the accelerometer and the proto board?  That should be done via the sketch, correct?

Correct- no soldering necessary, unless you want to use the optional interrupt lines, if you now have a board with that- those will need to be wired up to a proto board(typically to IO pin 2 or 3). Our example code should work when you start it up with the accelerometer plugged in.