go to your root folder (root explorer app via the market $1.82 US money) >>>data>>>>apps and find any icon packs you might have.
copy that whole app to sdcard>>>dcim.
use astro to extract the icon pack then copy the res file (in astro you will be able to see the icon) within it to a new folder in dcim i.e. Ibox icons.
then you HAVE to go delete the app you extracted. if you don't...it hangs your gallery. i created a folder just to put the apps i want to extract in so it's an easy delete.
then you can choose a custom icon from your gallery instead of installed apps. i freed craploads of space doing this. also you can go thru and delete all the stupid icons you wont be using so you don't have to scroll through hundreds just to find one. good luck.