Handling DirectX 9 texture

I would like some sample code which demonstrates how can I modify
a DirectX 9 texture. I have a texture, like a billboard, and I would
like to draw on that.

I already looked on google, on different gamedev sites etc. haven't
found a working solution.

As a texture quad, here's a sample:
http://www.drunkenhy...er=2;article=30

If I try to modify the loaded texture, whatever I try
(UpdateTexture, UpdateSurface, different D3DUSAGE, D3DPOOL,
etc.), it crashes (with the much telling D3DERR_INVALIDCALL
error).

I need explicitly DirectX 9 (not openGL), and possible without
the usage if D3DX (like D3DX sprites).

Thanks,
ElfQT