The same way other effects which don't use ".spr" files are animated - make a series of ".png" files and a ".xml" file defining these into a sprite.
From what I know, yes. Take a look at the sprites for the female hero, or for pretty much anything added in the expansion packs.
Wow. I had no idea you could do this for thrown animations either. Maybe I didn't waste my time on those lava lamp and pokeyball animations after all. My only question is how do you reference the .xml or .spr file in your itemDB.xml? I'm familiar with creating .xml files for monsters, but in my itemDB file, do I just say thrown="items/thrown_lava_lamp.xml" instead of thrown="items/thrown_lava_lamp.png"? If so, can this trick also be used to animate iconFiles for items sitting on the ground as well?
Most animations have an associated XML that specifies all the frames. The DB then references the XML file at the appropriate time. Take a look at some of the current effects to get a good idea of how it works. (I would be more explicit, but it's been a while and I don't exactly remember. I think it was either props or effects that animated WITHOUT an XML at a fixed framerate. :X Honestly the best way to learn this stuff is to see how things already in the game are implemented.)
I think it's both. I had always therefore assumed that creatures were the only thing that could be animated with an xml.
Yes, it is both. Generally anything that would be considered completely "static" in its animations (as in, there is no need to change the frame-rate on a frame-by-frame basis) could function like that, and in DoD such things are effects and props. It's probably why they made them work like that. Albeit from what I know, it is usually supposed to work at changing frame-rate if you do it the longer way (with the ".xml" file) - it's just unnecessary for the most part.
