Once you signup for groundschool at whatever training facility you decide to go with, Blake, I'm sure that they would let you write the radio licence right away at no cost.
However, if there is any doubt in their minds that you won't become a paying student, they may want to charge you for administering the test, so I'd hold off untill you are firmly established somewhere.
Up untill your solo, you don't need the licence anyways as your instructor is the PIC. He/she will likely (Should) have you making radio calls regardless, but you
can legally do so without your radio licence at that point since you are a student, and not the PIC.
In other words, once you start training make sure to get the radio licence and PSTAR out of the way quickly, but untill then there is really no pressing rush for either.
Then again, Blake, having been following your blog, I know you are going to be a very enthusiastic student, so I understand why you want to get ahead with these things.
