You really don't need a tripod, just a way to ensure that the camera doesn't move, like a hard, flat surface. I also sugest that you try using more frames for walking. This website (
http://stopmotioncentral.com/brickfilms-basics.html) gives some simple instructions on how to accomplish that. I get a lot of sound effects from
http://www.findsounds.com/types.html. I look forward to seeing more animations!