My *Recently Added* songs aren't showing up in my Music Library? How Come?

More details are needed before anyone can offer much in the way of advice. What precisely do you mean by "recently added"? Do you mean tracks imported via iTunes from a CD, tracks you dragged into the iTunes Music folder, or what, exactly?

Are the songs in the 'Recently Added' playlist?

If not, try going along the top of the screen and choosing File>Add Folder to Library, and add the entire folder with all of the songs in it, instead of clicking and dragging the folder into iTunes.