help with images editing (game sprites)

hello, I'm learning to make 2d games and so far I'm able to make them work. But I need help editing my sprites (2d images) I download "the GIMP", but I need to add an alpha channel to "BMP" format, but the gimp doesn't allow such a thing and the game design book I have says that it should be allow.

I also need to make the formats: BMP, DDS, DIB, JPG, PNG, and TGA. To allow animated sprites. (layer over layer) I can't do that in the GIMP.

something like this, but on BMP format or any other of the above formats.

http://www.infernox.net/zero.gif

http://www.infernox.net/megaman.gif


anyone has an idea of what i can do to accomplish this? (I don't have money for adobe photoshop)

Ok, from what I know, the only format animated Gifs can be in are GIF format. BMP, DDS, DIB, JPG, and TGA, are no nos, due to aliasing.
You can download Photoshop, with cracks, via torrent if you don't want to pay for it, but you need after effects to animate.

Other wise you can make all the frames in GIMP (it is possible) and then download a free gif maker, like unlead or Microsoft gif maker.

please delete I found everything I needed.