Hi!
Are you attempting to use the icon from one file to paste to another file? If so, try this:
Highlight the file with the icon you want to use and key in cmd+i to bring up Get Info. Click on the icon at the top of the Get Info wondow and key in cmd+c to copy it. Highlight the file that you want to paste the icon to, do cmd+i, highlight the icon in the get Info window, then key in cmd+v to paste it to this file. The icon will be the proper size to begin with, since it was a file icon to begin with. (The way shown in the preceding post should also work, but insure that you highlight and copy the graphic icon image first, before trying to paste it into the other file.)
If you want to use a custom graphic that is not an icon, I found a simple way to convert file preview images to icons using Pic2Icon. I keep it in the Dock and drop a graphics file (or folder's worth of graphic files) on it and it immediately changes the generic icons to icons with the graphics on them. This freeware utility was developed by SugarCube Software, but is no longer available on the web, even though Googling will provide plenty of links. However, they were nice enough not to originally restrict it's redistribution and I have a copy on my iDisk if you want it. The link is posted below and the archived file will immediately begin downloading if you click on it. (I'll leave the link active for a few days or so before disabling it.)
http://homepage.mac.com/majordadusma/filechute/pic2icon.dmg.sit
You can also create such preview icons via Photoshop, if you have it...
Gary
1GHz DP G4 Quicksilver 2002, 400MHz B&W rev.2 G3, Mac SE30 Mac OS X (10.4.5) 5G iPod, Epson 2200 & R300 & LW Select 360 Printers, Epson 3200 Scanner