You may need to get more specific. Some of the tablets get pretty small and phones pretty big, exceeding the size of some tablets. Figure out a size you're looking for and do a Google search for that size Android Tablet. There are a few pretty small ones but you didn't say how small or what you consider cheap.
On a related topic, I just picked up an LG phone from Walmart (Straight Talk branded), for $10.00. Wouldn't make much of a tablet, due to limited memory, but it should make a dandy music player.
Now all I need to do is fire up the desktop to transfer my files.