Save files are kept in a different place than the game itself, so if you already reformatted, then it's too late to recover them.
At best, you could ask someone here for their save games that may happen to be near where you were at.
At worst, you could start over from the beginning. Depending on how far you were, it could be worth it to avoid the hassle.
At... middle?, you could use SpoilerAL to cheat your way back to where you remember yourself at before you lost your save files. If you go with this, be careful not to get carried away and cheat your way to omnipotence.
