RadoX ... use photoshop. first this you should do is have each one of those icons in a layer separate from the background.  then color the entire background black.  then in channels pane add a new one.  this will be the alpha chanel.  then select your icons by ctrl-clicking on their image in layers pane.  with the icons selected go to the new channel you created and press Ctrl-Delete this will create a white hole the shape of your icons on the alpha channel.  then just save it as bmp and you're set. 
 
heres a sample: 
 
toolbar.rar