If you do change anything remember to write down what you already do so that you can get back to it, but I would stick with what you are already doing unless you want to play for the fun of it.
The one I have at hand is Adobe Photoshop 6 for Photographers by Martin Evening. Even though it is for PS 6 the techniques may be transferable to Elements.
I have just looked for more photoshop books and I can't find any so I may have loaned them out and not had them back, If I come across them I will include them.
Peter