This is one of the lesser known functions in Firefox, but is one of the most helpful. By doing this you will no longer have to use search toolbars in order to quickly search a website. For this example I will use Wowhead.
Step One: Go to Wowhead.com On the main page where you see the search bar, right click inside the bar and click "Add a keyword for this search".
Step Two: Now a box will pop up like the one in the screenshot below. For the name, put Wowhead. For the keyword you can put whatever you want. Try to pick something relevant and short, I chose "wh". For Create In you can put it in a new folder if you want for organization, but this isn't required.
Step Three: And that's all you have to do. In your address bar you can type "wh terokk's quill" or whatever you want to search for, and you will automatically be brought to the item's page.
As you can see this is much easier then having to find/download a toolbar in order to search for something. This will also work with (to my knowledge) every search bar. So you can use this method for google, youtube, wikipedia, or whatever you like.
If you have any questions feel free to post them.