The whole "dedicated server" ballyhoo has brought the PC gaming community into an uproar with developers opting for internet matchmaking to release their games out faster. Aliens Vs. Predator has matchmaking out of the box but developer Rebellion appears to have a change in plans for AVP as they are rolling out dedicated server support for the PC version very soon.
Over at the Steam forums, a representative from Rebellion has confirmed a beta release with reduced functionality will be available in a few days. Added features and the usual assortment of bug fixes will be released over the next few weeks. If you're interested in running a server, it will be under the "Tools" tab in the Steam client as a free download.
Those who wish to keep tabs on further developments are urged to keep an eye on the thread at the Steam forums (provided in the source link). In the meantime, you could finish up the single-player campaign or try your luck with the current matchmaking feature.