Lost firefox Icon graphic [SOLVED]

[ezas]

I was playing around with the task bar and the menu in KDE 4.4.1 (2010) and I right clicked on Firefox in the menu and selected add to panel. It added but way over to the right. (a couple of days ago it added right next to the other panel icons). So tried right clicking firefox in the menu and selected add to desktop which it did but the Icon turned to a question mark. I've been clicking around trying to figure out how/where to point to pick the firefox icon back up. I'd also like to put firefox back in the menu. In  Win I would navigate to the executable but I don't know if it works the same way in Linux and I can't see where you change the icon anyway. I click on Icon settings but I don't see where/how you set the icon graphic.

Any help appreciated

I solved the problem by restoring the menu to the system menu. That put firefox back in the menu along with its icon. Close enough for me.

[ezas]

I went ahead and added firefox to the panel again and figured out that clicking panel options lets you move icons around. Got things set the way I want now.

[hal8000]

Yes, its right click an icon, then left click panel options, then left click panel settings. Only then does the drag pointer appear.

I've just added konsole to the panel and got a red cross, it says unable to load widget, could not find icon.
Any ideas on where the icons for widgets are stored?