You import the commands you need from the dbpro dll it is in. They are equivalent to their GDK counterparts, I use the DarkGDK naming convention so that I can compile lib/dll with dbpro or gdk with only minor changes.
You will get all the info you need in the dll section, lots of demos etc.
Here is a quick feel for what you need to do.
Globals.h
Creates function pointers which we will later set to the dll functions.
typedef IDirect3DDevice9* (__cdecl *dbGetDirect3DDevicePtr_t) ();
extern dbGetDirect3DDevicePtr_t dbGetDirect3DDevice;
typedef sObject* (__cdecl *dbGetObjectPtr_t) (int);
extern dbGetObjectPtr_t dbGetObject;// = 0;
typedef void (__cdecl *dbGetObjectWorldMatrixPtr_t) (int, int, D3DXMATRIX*);
extern dbGetObjectWorldMatrixPtr_t dbGetObjectWorldMatrix;// = 0;
typedef void (__cdecl *dbSetObjectWorldMatrixPtr_t) (int, D3DXMATRIX*);
extern dbSetObjectWorldMatrixPtr_t dbSetObjectWorldMatrix;
typedef void (__cdecl *dbPositionObjectPtr_t) (int, float, float, float);
extern dbPositionObjectPtr_t dbPositionObject;
typedef void (__cdecl *dbRotateObjectPtr_t) (int, float, float, float);
extern dbRotateObjectPtr_t dbRotateObject;
typedef bool (__cdecl *dbObjectExistPtr_t) (int);
extern dbObjectExistPtr_t dbObjectExist;
typedef bool (__cdecl *dbLimbExistPtr_t) (int, int);
extern dbLimbExistPtr_t dbLimbExist;
importdll.h
// Populate the function pointers for your DLL's
dbGetDirect3DDevice = (dbGetDirect3DDevicePtr_t)GetProcAddress(g_hLib, "?GetDirect3DDevice@@YAPAUIDirect3DDevice9@@XZ");
dbGetObject = (dbGetObjectPtr_t)GetProcAddress(Basic3D, "?GetObjectA@@YAPAUsObject@@H@Z");
dbGetObjectWorldMatrix = (dbGetObjectWorldMatrixPtr_t)GetProcAddress(Basic3D, "?GetWorldMatrix@@YAXHHPAUD3DXMATRIX@@@Z");
dbSetObjectWorldMatrix = (dbSetObjectWorldMatrixPtr_t)GetProcAddress(Basic3D, "?SetWorldMatrix@@YAXHPAUD3DXMATRIX@@@Z");
dbPositionObject = (dbPositionObjectPtr_t)GetProcAddress(Basic3D, "?Position@@YAXHMMM@Z");
dbRotateObject = (dbRotateObjectPtr_t)GetProcAddress(Basic3D, "?Rotate@@YAXHMMM@Z");
dbLimbExist = (dbLimbExistPtr_t)GetProcAddress(Basic3D, "?GetLimbExist@@YAHHH@Z");
dbObjectExist = (dbObjectExistPtr_t)GetProcAddress(Basic3D, "?GetExist@@YAHH@Z");