There is a tool from Telegraphics called PSDParse that should do the trick.
psd2png.exe -w Filename.psd usage: psd2png.exe [options] psdfile... -h, --help show this help -v, --verbose print more information -q, --quiet work silently -w, --writepng write PNG files of each raster layer (and merged composite) -d, --pngdir dir put PNGs in directory (implies --writepng) -m, --makedirs create subdirectory for PNG if layer name contains \'s -l, --list write an 'asset list' of layer sizes and positions -s, --split write each composite channel to individual (grey scale) PNG
Here's a link to the version I used, or you can go to the website for the latest version for your operating system.
http://www.telegraphics.com.au/sw/files/psdparse-1.7b1-win.zip