The title of this cache contains references to three pieces of fiction. What you need to do is figure out what they are and who created them. Then take the first three letters of their last names arranged in the same order that the pieces of fiction associated with them appeared to the public and assign numbers to them starting with two.
Example:
So for instance if the Names were Austen, Darwin and King your letter=number combinations would be
A=2 U=3 S=4 D=5 A=6 R=7 K=8 I=9 N=0.
Now just substitute your numbers for the letters in these coordinates.
38.ARCCEE° -120.AMACMD°
You can check your answers for this puzzle on GeoChecker.com.