So, an hour or so of fiddling and trying different libraries, and it seems OIS (and SDL) just recognises the controller as a joystick and provides me with everything I need.
If you install OIS from the link above, and make/run the 'ConsoleTest' project, you can see the output from the controller in the debug window.
Additionally, here's enums i've been using that match to the axes/button numbers produced by SDL (note not OIS, which i've now decided not to use, numberings could well be the same). Notice that the trigger buttons are not classified as an axis, which i'm pretty sure they should be (0-255 from memory):
//Values SDL attributes to individual PS3 axes
enum EPS3RawAxesIndex
{
EPS3RawAxesIndex_LeftX = 0,
EPS3RawAxesIndex_LeftY = 1,
EPS3RawAxesIndex_RightX = 2,
EPS3RawAxesIndex_RightY = 3
};
//Values SDL attributes to individual PS3 controller buttons
enum EPS3RawButtonIndex
{
EPS3RawButtonIndex_Select = 0,
EPS3RawButtonIndex_JoyClickLeft = 1,
EPS3RawButtonIndex_JoyClickRight = 2,
EPS3RawButtonIndex_Start = 3,
EPS3RawButtonIndex_DpadUp = 4,
EPS3RawButtonIndex_DpadRight = 5,
EPS3RawButtonIndex_DpadDown = 6,
EPS3RawButtonIndex_DpadLeft = 7,
EPS3RawButtonIndex_TriggerLeft = 8,
EPS3RawButtonIndex_TriggerRight = 9,
EPS3RawButtonIndex_ShoulderLeft = 10,
EPS3RawButtonIndex_ShoulderRight = 11,
EPS3RawButtonIndex_Triangle = 12,
EPS3RawButtonIndex_Circle = 13,
EPS3RawButtonIndex_Cross = 14,
EPS3RawButtonIndex_Square = 15,
EPS3RawButtonIndex_PSButton = 16
};