Right now DirecTV only has CBS and NBC out of NY and LA. To get them you must live in a white area (not served by any local stations), live in an O&O (the local station is owned and operated by the network) area or get a waiver from your local affiliate. If we are lucky, Fox HD will be added any day. Don't hold your breath for ABC though. The executives have made it clear they don't want a similar setup.
Sometime in '05, DirecTV is launching a new satellite that has the capability of carrying HD locals. As usual, they will start with the top markets and work their way down to the smaller ones.
Most people just use an antenna to get their locals in HD. They are seamlessly integrated into the DirecTV guide.