http://www.gametrailers.com/video/sdcc-09-left-4-dead/53209

http://www.etsy.com/view_listing.php?listing_id=27382100

Hey guys,

Most of you are probably already aware that there is a chatroom built-in on Steam that could be used as kind of an old-school IRC chatroom... but no one's using it!

It's particularly useful in arranging matches, meeting new people, and really, talking to one another!

I therefore invite y'all lazy bastards to go there and chat. Go idle for months, talk like a drunken maniac, or act like a total douche - it doesn't matter. We want EVERYONE to use the chatroom!

Ta

Go to the 'Tools' tab, and you should see an entry named "Left 4 Dead Authoring Tools Beta." Click it, then choose 'Install'.

From L4D.com:

"Today we are opening the beta of the Left 4 Dead Authoring Tools to the public. It is available as a free download for all owners of the PC version of Left 4 Dead, and can be found under the "Tools" tab in Steam.

The L4D Authoring Tools include modified versions of the same tools we used to produce Left 4 Dead.

Using the L4D Authoring Tools, you may create your own campaign maps, character skins, 3D models, sound effects, and music and load them into the game."


More at http://www.l4d.com/blog/post.php?id=2510

Read the release notes. Those who have their own servers, check to see if you're using the most current version (v1.0.1.3). Use a program called HLSW for more info.