When a creature is successfully targeted by an effect that transports the creature to another plane but no location on that plane is specified, where does the creature arrive?
If the plane is the Seven Mounting Heavens of Celestia creatures "always find themselves in the surf of an ocean surrounding Mount Celestia" (MP 133), but does a canonical Dungeons and Dragons 3.5 list of these--let's call them--arrival points exist? A homebrewed, third party, or other edition's arrival points list is awesome, too, if a canonical 3.5 one's unavialable or, in your opinion, terrible.
When an effect causes transportation from the Prime Material Plane to a coexistent plane (e.g. the Ethereal Plane, the Plane of Shadow), I assume the arrival point is the equivalent point on the coexistent plane that target creature occupied on the Prime Material Plane, but I'd enjoy this bold assumption disproved.
If the creature is transported at random to another plane (e.g. the spell reality maelstrom [evoc] (SpC 168-9), the supernatural ability portalwake of the teratomorph (MM2 194)), the chart Random Planar Destinations (SpC 169) leaves the "layer and exact location on the particular plane... up to the DM," but that's less than helpful to the DM of a PC who has little information about--but nonetheless wants to travel--the planes.
You move yourself or some other creature to another plane of existence or alternate dimension. If several willing persons link hands in a circle, as many as eight can be affected by the plane shift at the same time. Precise accuracy as to a particular arrival location on the intended plane is nigh impossible. From the Material Plane, you can reach any other plane, though you appear 5 to 500 miles (5d%) from your intended destination.
The the Dungeon Master's Guide adds that the spell plane shift "deposits the spellcaster on the first layer of the plane" (151), but it's silent about where on that plane, and some of those planes are infinite.
My House Rules
In the spells plane shift and teleport [conj] (PH 292-3) et. al. the destination is generally where the creature wants to arrive, while a location is the the most obvious or common entrance to a named site. In my games prior to using a general teleportation effect like teleport or plane shift a destination must be designated as either a location, layout, or object. (Exempted are specific teleportation effect like citygate [trans] (Dragon Compendium Volume 1 62), door to great evil [conj] ("Ghostwalk Web Enhancement" 6), and gemjump [conj] (SpC 101).) If your house rules define destination and location differently, that's cool, but try to answer with mine in mind.