Grabbed from this url (may only contain most useful definitions): http://www.groupsrv.com/dotnet/about52848.html:
WM_NULL = 0×0000,
WM_CREATE = 0×0001,
WM_DESTROY = 0×0002,
WM_MOVE = 0×0003,
WM_SIZE = 0×0005,
WM_ACTIVATE = 0×0006,
WM_SETFOCUS = 0×0007,
WM_KILLFOCUS = 0×0008,
WM_ENABLE = 0x000A,
WM_SETREDRAW = 0x000B,
WM_SETTEXT = 0x000C,
WM_GETTEXT = 0x000D,
WM_GETTEXTLENGTH = 0x000E,
WM_PAINT = 0x000F,
WM_CLOSE = 0×0010,
WM_QUERYENDSESSION = 0×0011,
WM_QUIT = 0×0012,
WM_QUERYOPEN = 0×0013,
WM_ERASEBKGND = 0×0014,
WM_SYSCOLORCHANGE = 0×0015,
WM_ENDSESSION = 0×0016,
WM_SHOWWINDOW = 0×0018,
WM_CTLCOLOR = 0×0019,
WM_WININICHANGE = 0x001A,
WM_SETTINGCHANGE = 0x001A,
WM_DEVMODECHANGE = 0x001B,
WM_ACTIVATEAPP = 0x001C,
WM_FONTCHANGE = 0x001D,
WM_TIMECHANGE = 0x001E,
WM_CANCELMODE = 0x001F,
WM_SETCURSOR = 0×0020,
WM_MOUSEACTIVATE = 0×0021,
WM_CHILDACTIVATE = 0×0022,
WM_QUEUESYNC = 0×0023,
WM_GETMINMAXINFO = 0×0024,
WM_PAINTICON = 0×0026,
WM_ICONERASEBKGND = 0×0027,
WM_NEXTDLGCTL = 0×0028,
WM_SPOOLERSTATUS = 0x002A,
WM_DRAWITEM = 0x002B,
WM_MEASUREITEM = 0x002C,
WM_DELETEITEM = 0x002D,
WM_VKEYTOITEM = 0x002E,
WM_CHARTOITEM = 0x002F,
WM_SETFONT = 0×0030,
WM_GETFONT = 0×0031,
WM_SETHOTKEY = 0×0032,
WM_GETHOTKEY = 0×0033,
WM_QUERYDRAGICON = 0×0037,
WM_COMPAREITEM = 0×0039,
WM_GETOBJECT = 0x003D,
WM_COMPACTING = 0×0041,
WM_COMMNOTIFY = 0×0044 ,
WM_WINDOWPOSCHANGING = 0×0046,
WM_WINDOWPOSCHANGED = 0×0047,
WM_POWER = 0×0048,
WM_COPYDATA = 0x004A,
WM_CANCELJOURNAL = 0x004B,
WM_NOTIFY = 0x004E,
WM_INPUTLANGCHANGEREQUEST = 0×0050,
WM_INPUTLANGCHANGE = 0×0051,
WM_TCARD = 0×0052,
WM_HELP = 0×0053,
WM_USERCHANGED = 0×0054,
WM_NOTIFYFORMAT = 0×0055,
WM_CONTEXTMENU = 0x007B,
WM_STYLECHANGING = 0x007C,
WM_STYLECHANGED = 0x007D,
WM_DISPLAYCHANGE = 0x007E,
WM_GETICON = 0x007F,
WM_SETICON = 0×0080,
WM_NCCREATE = 0×0081,
WM_NCDESTROY = 0×0082,
WM_NCCALCSIZE = 0×0083,
WM_NCHITTEST = 0×0084,
WM_NCPAINT = 0×0085,
WM_NCACTIVATE = 0×0086,
WM_GETDLGCODE = 0×0087,
WM_SYNCPAINT = 0×0088,
WM_NCMOUSEMOVE = 0x00A0,
WM_NCLBUTTONDOWN = 0x00A1,
WM_NCLBUTTONUP = 0x00A2,
WM_NCLBUTTONDBLCLK = 0x00A3,
WM_NCRBUTTONDOWN = 0x00A4,
WM_NCRBUTTONUP = 0x00A5,
WM_NCRBUTTONDBLCLK = 0x00A6,
WM_NCMBUTTONDOWN = 0x00A7,
WM_NCMBUTTONUP = 0x00A8,
WM_NCMBUTTONDBLCLK = 0x00A9,
WM_KEYDOWN = 0×0100,
WM_KEYUP = 0×0101,
WM_CHAR = 0×0102,
WM_DEADCHAR = 0×0103,
WM_SYSKEYDOWN = 0×0104,
WM_SYSKEYUP = 0×0105,
WM_SYSCHAR = 0×0106,
WM_SYSDEADCHAR = 0×0107,
WM_KEYLAST = 0×0108,
WM_IME_STARTCOMPOSITION = 0x010D,
WM_IME_ENDCOMPOSITION = 0x010E,
WM_IME_COMPOSITION = 0x010F,
WM_IME_KEYLAST = 0x010F,
WM_INITDIALOG = 0×0110,
WM_COMMAND = 0×0111,
WM_SYSCOMMAND = 0×0112,
WM_TIMER = 0×0113,
WM_HSCROLL = 0×0114,
WM_VSCROLL = 0×0115,
WM_INITMENU = 0×0116,
WM_INITMENUPOPUP = 0×0117,
WM_MENUSELECT = 0x011F,
WM_MENUCHAR = 0×0120,
WM_ENTERIDLE = 0×0121,
WM_MENURBUTTONUP = 0×0122,
WM_MENUDRAG = 0×0123,
WM_MENUGETOBJECT = 0×0124,
WM_UNINITMENUPOPUP = 0×0125,
WM_MENUCOMMAND = 0×0126,
WM_CTLCOLORMSGBOX = 0×0132,
WM_CTLCOLOREDIT = 0×0133,
WM_CTLCOLORLISTBOX = 0×0134,
WM_CTLCOLORBTN = 0×0135,
WM_CTLCOLORDLG = 0×0136,
WM_CTLCOLORSCROLLBAR = 0×0137,
WM_CTLCOLORSTATIC = 0×0138,
WM_MOUSEMOVE = 0×0200,
WM_LBUTTONDOWN = 0×0201,
WM_LBUTTONUP = 0×0202,
WM_LBUTTONDBLCLK = 0×0203,
WM_RBUTTONDOWN = 0×0204,
WM_RBUTTONUP = 0×0205,
WM_RBUTTONDBLCLK = 0×0206,
WM_MBUTTONDOWN = 0×0207,
WM_MBUTTONUP = 0×0208,
WM_MBUTTONDBLCLK = 0×0209,
WM_MOUSEWHEEL = 0x020A,
WM_PARENTNOTIFY = 0×0210,
WM_ENTERMENULOOP = 0×0211,
WM_EXITMENULOOP = 0×0212,
WM_NEXTMENU = 0×0213,
WM_SIZING = 0×0214,
WM_CAPTURECHANGED = 0×0215,
WM_MOVING = 0×0216,
WM_DEVICECHANGE = 0×0219,
WM_MDICREATE = 0×0220,
WM_MDIDESTROY = 0×0221,
WM_MDIACTIVATE = 0×0222,
WM_MDIRESTORE = 0×0223,
WM_MDINEXT = 0×0224,
WM_MDIMAXIMIZE = 0×0225,
WM_MDITILE = 0×0226,
WM_MDICASCADE = 0×0227,
WM_MDIICONARRANGE = 0×0228,
WM_MDIGETACTIVE = 0×0229,
WM_MDISETMENU = 0×0230,
WM_ENTERSIZEMOVE = 0×0231,
WM_EXITSIZEMOVE = 0×0232,
WM_DROPFILES = 0×0233,
WM_MDIREFRESHMENU = 0×0234,
WM_IME_SETCONTEXT = 0×0281,
WM_IME_NOTIFY = 0×0282,
WM_IME_CONTROL = 0×0283,
WM_IME_COMPOSITIONFULL = 0×0284,
WM_IME_SELECT = 0×0285,
WM_IME_CHAR = 0×0286,
WM_IME_REQUEST = 0×0288,
WM_IME_KEYDOWN = 0×0290,
WM_IME_KEYUP = 0×0291,
WM_MOUSEHOVER = 0x02A1,
WM_MOUSELEAVE = 0x02A3,
WM_CUT = 0×0300,
WM_COPY = 0×0301,
WM_PASTE = 0×0302,
WM_CLEAR = 0×0303,
WM_UNDO = 0×0304,
WM_RENDERFORMAT = 0×0305,
WM_RENDERALLFORMATS = 0×0306,
WM_DESTROYCLIPBOARD = 0×0307,
WM_DRAWCLIPBOARD = 0×0308,
WM_PAINTCLIPBOARD = 0×0309,
WM_VSCROLLCLIPBOARD = 0x030A,
WM_SIZECLIPBOARD = 0x030B,
WM_ASKCBFORMATNAME = 0x030C,
WM_CHANGECBCHAIN = 0x030D,
WM_HSCROLLCLIPBOARD = 0x030E,
WM_QUERYNEWPALETTE = 0x030F,
WM_PALETTEISCHANGING = 0×0310,
WM_PALETTECHANGED = 0×0311,
WM_HOTKEY = 0×0312,
WM_PRINT = 0×0317,
WM_PRINTCLIENT = 0×0318,
WM_HANDHELDFIRST = 0×0358,
WM_HANDHELDLAST = 0x035F,
WM_AFXFIRST = 0×0360,
WM_AFXLAST = 0x037F,
WM_PENWINFIRST = 0×0380,
WM_PENWINLAST = 0x038F,
WM_APP = 0×8000,
WM_USER = 0×0400,
WM_REFLECT = WM_USER + 0x1c00