I've bought a dedicated l4d2 server located in Albany NY. If you want to use it, the LOBBY LEADER needs to do the following BEFORE creating a lobby. Enable develope console in multiplayer options. Hit ~ to bring up your console and type in:

mm_dedicated_force_servers 208.85.5.238:27016

all as one line. Then hit enter in console.
Then create a lobby like normal. This will guarantee your lobby uses my server everytime.

If the server is currently in use, this won't work. You need to enter this command everytime you reboot the game, or bind a key to it. See the Vindictive Forums for more details.