Ok, just went through the procedure myself, go to woah, to make sure it works. It does, but I'm sorry to say the def's on the Download.com site are already out of date. Current definitions are for the 12/10/06.BEFORE PROCEEDING check any new posts underneath, in case some kind guru has posted a better way of doing this. A guru I aint.
Anyway, open ExtractNow. One of the bottom tabs is "settings". In general,you might want to tick "save list on close," and "associate with zip files in explorer" Underneath that is a window showing options for where the files are extracted to. I think it defaults to the Extract now program folder. Have a look, see where it goes on yours. That's where to look for your files. Each time you unzip a file, you can specify where it goes by using the browse button, (grey rectangle, two dots at the bottom centre). What your looking for is titled defs.ref, is about 776kb. Remember where to find it. Now open the Lavasoft program file (usually: My computer> Local Disk C:/> Program Files>Lavasoft>Ad-Aware SE Personal.) In it you'll see, amongst other things, "defs.ref" and "defs.ref.old" (It keeps the last defs as a backup). Delete the old defs. Rename the defs. "defs.ref.old". Use the same format/lowercase that were there already. Find the defs you just unzipped. Right click, select "cut". Go back to the AdAware folder in program files, right click in a blank area of the folder, select paste. "defs.ref" will appear. Lavasoft will use these definitions. How it knows to use them is via a process known in Lavasoft circles as "magic". Are you still awake? Just decided to throw a bit of colour in to break it up a bit. Other things you might see in that folder are 2 or 3 other folders, titled "language, skins, plugins, depending on what options you have. Also "install log, license.txt, AdAware.exe, unregaaw.exe, UNWISE.exe. and an alert.wav (which if clicked upon makes a juicy fart.) If there's anything else in there, let me know, please.
I've found in the past that just the action of doing this "resets" it somehow so it downloads updates ok. Don't know why.
Now open the program. a window will open, bleating that your definitions are (26) days out of date. Try connecting for new def's now. Hold your breath, but pretend to be a bit "couldn't-care-less" about it. (Unless you've got a Dell. Then you should plead with it, beg and genuflect, maybe spill a drop of blood onto the casing/promise it your firstborn etc etc) Hope like hell this works. Good luck.