First off all... welcome
Second ADF files are not packed.. they are diskimmages and WinUAE take them as they are (if you where to use them with an Amiga you would need a tool to write them back onto a disk ofcause).
Workbench 3.9 is the latest version and is sold on a CD in every Amiga store on the planet I would think... almost anyway. I think you should try to collect the small amount of money this software cost and buy it. Anyway.. to be able to use this CD you will have to either install 3.x with CD support or have a bootdisk with CD support on it to boot the CDrom.
But if you miss the old thing then why not run it on a real Amiga instead of emulation? An A1200 can now and then be found for as little as 40$.
