Can't load .el files

[JS <d44sf@44ada.com>]

I have tried to put the following two .el files in my load path:

tabbar.el
pc-bufsw.el

In my .emacs file I have writtin:

(require 'tabbar)
(require 'pc-bufsw)

But when I restart emacs I get this error:


An error has occurred while loading `/home/johs/.emacs':

File error: "Cannot open load file", "tabbar"

To ensure normal operation, you should investigate the cause
of the error in your initialization file and remove it.  Start
Emacs with the `--debug-init' option to view a complete error
backtrace


-------------------------

I also have setnu.el in the same load path and it works fine, I have this in
my .emacs file for setnu:

(require 'setnu)
(global-set-key "\C-cl" 'setnu-mode)

Why can't I load the other modes?