Plenty of good advice up there.  I may not be a noobie, having started with Poser 3, but I sure ain't an expert either.

I wish someone had long ago hinted that before I've downloaded around 20 - 30 Gigs of Content I should make sure where the textures disappear to (like that guy's socks in another Forum) because often, too often, a dress Zip file may be called Ziggies V4 Dress and the texture itself is called Uncle Charlie's Sexy V4 dress.

I now run an Excel spreadsheet with all names and all LOCATIONS of stuff I download.  This may be overkill but it works.  Like I say, an expert I ain't so there is bound to be a simpler way to find your several-year-old dress tex the next time you'd like to modify it.