gah my entire lengthy reply was just eaten so here goes more of a response ben:
didnt mean to be flip earlier its just that some of us maybe most of us who have dug around for art have been doing so for years. it can be time consuming but rewarding and i just wish it was as easy as 'pointing you to it'.
here is the process i use: because you know the style you are looking for, it makes this easier. goldbox series came out in a specific era of gaming, so start there. some of this was when ega was going vga, and some titles offer both, though the vga quality of these is questionable. the vga only titles were far more interesting artwise, in my own opinion. so: look for titles from the same era, late 80's early 90's. the bards tale and might and magic series arent too goldboxy, but stronghold and the summoning have some good things. also, ports to other platforms like amiga and gameboy advance can contain better graphics and art resources that dont appear in the pc version. this is true for eob series and pool of radiance off the top of my head. don't discount looking through shareware or modded or homemade games either. ive found quite a bit to work with over the years among those strange and wonderful unique games. also, modding communities can usually offer new or refurbished ('updated' games!) art and often in very large amounts. if you really are gung-ho about it, i would also suggest taking the time and effort to teach yourself the basics of graphics format ripping, so you can explore things for yourself as well. its not really all that difficult and there are some excellent programs developed just for viewing/capturing/reformatting. another suggestion would be to look at games that come moddable, such as the myriad roguelikes like nethack or dwarf fortress, and browse all the glorious fanmade art available for them. try searching for different format/genre game art, like that from sega genesis (a very appropriate-era art style platform) or supernintendo. search for sprites on google and browse the images, or visit the numerous modding/fan/shrine sites that offer galleries of downloadable/saveable sprite sheets. many of these game include intro art or animations or any number of different things besides player/creature spriting. finally, another great place to look for a lot of art in one place would be for dungeons and dragons tabletop gaming. lots of icons can be found in central places for adding/printing to paper stock in lieu of using figure minis (some would call this a sacrilege i know but it exists
) and browse through those. the great thing about going this route is much of the work has been done for you as far as isolating specific pieces and then labelling it clearly in d&d terms as to what it is, ie: a harpy being a harpy. if you don't already have one, a good solid art viewer/manipulator is your best friend. i don't see the need to spend cash for this, as there are so many quality programs out there made by someone so why not use one? i use irfanview myself, as it allows collating of art and then i can change color depth and pixel size by the batchful.
okay sorry bout all that just didnt want to be glib but also didnt want you to think there isnt a way to do this. like everything, it just takes some time. on the negative side, there is probably some art out there that someone wants to keep to themselves, but on the positive you can give yourself the tools to dig up what you are looking for too. i know you have little time these days but i hope this helps some. i can provide specific links to some of what i suggested above and i can do so privately if you would prefer.
(edited because of mispellings and for clarity)