With 70,964,907 .COM domain names registered (see Name Intelligence's Daily Changes), the name you want is already taken. Even names you wouldn't want in a million years are taken. Names so silly that you'd be embarrassed to use them as the address for your site are taken, and this has been true for many, many years. It's why tech companies end up naming themselves things that look like typographical errors, like "Flickr" or "Joost" or just about any other Web 2.0 company you might find on the TechCrunch index. 

This is where the aftermarket comes in. The aftermarket allocates registered and expired domain names to new registrants looking for a name they couldn't otherwise register as a new name. 

The aftermarket is also a good place to pick up a typographical error name.