I have recently begun to run emacs in
-nw mode and ran in into a problem when I started to open up more than 2 frames. The third frame became really crapped in between. So I wonder how I can change the frame width like I could do when I used emacs' GUI
I assume you mean windows, not frames, since a frame means another X window in X mode, and functions more like saving and restoring the window state in text mode.
You can click on the window status line and drag it just like you can in X ( if your terminal supports a mouse ), or you make the current window taller with