you can started by issuing kicker in an Xterm, but I think if you lost the panel and there is no Konsole/Xterm shortcut on your desktop it would be hard to do so, wouldn't it? So anyway the problem solved only temporarely, there are numerous possible causes, hence there are many fixes, I'd go for the most destructive, no I am not talking about reinstalling whole OS or KDE - this is a prerogative of another so-called OS, I am talking about you losing all the preferences for KDE you might have, but not necessarily - you can back up whatever you think is important. So to the point - remove ~/.kde directory - switch to another virtual console Ctrl-Alt-F1 ... F6, login as the user that having problems with kde kicker and issue
rm -rf .kde/
restart X, go back to kde and everything will be restored to its defaults.
Have fun, and don't forget to make backups.