Never mind!!!  I figured it out!! I actually did download some default skin replacements a few years ago and I forgot. I guess when I used the skintone selector it activated them or something. So happy I found them, thank you so much for your help. Ha ha I feel dumb.

That's the thing I have a problem with, I don't what file! I downloaded Christian Love's Custom skintone selector and in game I selected maxis and tan for one sim and automatically all of my sims changed from the regular skintones from game to custom ones. I like that it did that, but I don't like the color of one of the skintones and I want to change it. (thats why i'm here lol) So I'm not sure. Should I open Christian Love's Custom skintone selector which is actually an item? 

Once you have the file, how do you open it in SimPe?  Where is it located? Btw thanks for replying!!

Thank you so much for this tutorial, I have managed to do everything so far but now I'm stuck on importing  the new textures. You say to open the default skin replacement file that will be the "host" for your new texture files  but I don't know where to find that! I tried to figure out by exploring around SimPe, but I never found any texture files. Please help! Sorry but I'm not that tech smart. Anyone know where to find it? Thanks in advance!