One of the fastest ways to create a free instant logo is to use a free logo generator.
Available both online and offline.
The offline offers software for download. If you're on a slower connection, or you need a longer time to decide on a right logotype. Download a free software to try in out.
There are many of those available if you do a search at any search engines. However, on this site, I'd publish results of the 2 of the better logo generators which I had tried.
Go to this site for the online free logo generator: cooltext.com
Choose the font, the color, the background and you have an instant logo in a "few minutes".
You could produce a pretty cool logo without messing with the selection. If you're in a hurrry, choose default.
Since Jan 06, cooltext has improved on its interface. The site now looks neat, with images sizes reduced and selection is much easier. Go take a look.
This is the first logo created with the following setting:

This is how it looks after I removed the bottom reflection.

And a few other logos created after going through some font selection.
This one that's carved on stone;



All default setting

Patience is required ...
.....if you opt for anything other than the default setting. And there's no way to preview your selection.
Rendering of each image takes only about 10 seconds. But some pages take ages to load. Though logos can only be created from fonts provided, there's plenty to choose from.
If you still can't get what you want, worry not. Let me introduce you...