Placing a small bitmap image inside a bigger bitmap image

I have this problem:

I want to place an image inside the canvas of another image, the problem is
that I want to be able to rotate the smaller image before pasting it.  So I
need something like StrechDraw but with the ability to specify a rotation

Also, Anyone knows something about Alpha channels ?, Does delphi allow the
creation of images with an Alpha channel ? (4 bytes per pixel ), I want to
use the bitmaps with OpenGL, so I need desperately to include transparency
information along with the picture information.

 Thanks in advance.
                             Ricardo Sarmiento