I have read that Neutrals are the best alignments for Sorcerers. I am wondering what alignment would fill on encompass a sorceress that has a terrible background that led to her becoming a criminal/spy for The Fates. I just made her yesterday due to my first campaign having a strong possibility of going south! Heh… Help! I have no idea what direction I want her personality to be. Everything else is set. I just can’t quite put “who is she?” in my head. 

If the fates represent cosmic order you may wish to be lawful.

Alignment determines which supernatural forces your character is aligned with.  Most epic fantasy stories center around conflict within some kind of cosmological duology.  The forces of good versus evil, tyranny versus freedom, or civilization versus anarchy to name a few.  If these questions aren't  relevant to your campaign your choice probably doesn't  matter.  Ultimately all personality types can be found in all alignments and class shouldn't factor in much at all.  

There's no right or wrong alignment for most classes, even typically "good" ones like Cleric or Paladin can be fully evil if you want.

What matters really is what your character's motivation is. For example, evil doesn't need to mean your character is a cackling maniac who tries to kill everyone they meet. I recently played a neutral evil sorcerer and settled on that alignment on the basis that he is ruthless, and has no qualms about killing to achieve his goals, but that doesn't mean killing was always his first choice. He had no problem working with others as long as it was furthering his goal (of ending a curse placed upon him, which they didn't know).

Criminal/spy is a bit complex because it will depend what you do; if you may have been required to kill innocents then that's tending towards evil (but could again be on the ruthless end of the scale, rather than the "just can't get enough of murdering" end). If it's more about infiltration, information gathering etc. then some flavour of neutral may work unless your goals are especially selfless, though it depends what your ultimate goals are (if they're to oppose evil then good can still work).

If you haven't picked your character's ideals yet, many backgrounds have ideals that include recommendations on alignment, and can help to inform that; often picking from the sample traits, ideals etc. can help to build a character's personality as some will feel right, and you can always tweak them if none is a perfect fit.

Thanks, everyone! I found the solution fairly quickly after posting (within a few days time). Unfortunately, I did not see these responses until 2 years later but they will help me explain to others!