Does anyone else remember the old D&D Gazetteers? I vaguely remeber having a couple of them. They were 96pg paperback books covering a specific area of a world. If i remember they could be dropped into any campaign setting. I remember them being awesome!
I would love to see a return of this product line. (Paperback, b&w inside and all) Im sure it wont happen but they would super usefull. If you don't remember them check them out on Amazon. They rocked.
I definitely dig them. Dwarves of Rockhome was my favorite, but that’s no surprise.
I not only remember them, I'm still using them.
Most are available as PDF through dndclassics.com, and I've put together my own map combining the different areas detailed for personal reference - it's my group's current go-to campaign setting.
I'm not sure such a product would work these days though. Materials of this sort, even when able to be dropped into any campaign world, tend to cost enough to produce that the price required for decent profit margin makes the product feel too expensive to too many potential customers for enough sales to be made to actually generate a profit - especially because "can be dropped into any campaign world" inevitably proves to be A) not accurate because it requires a lot of changing details to get things to fit, or B) true, but at the expense that the info in the book is entirely bland and unexciting because it doesn't commit to any one style or theme.
I remember those they were full of great material. I vote bring them back.
There is a Mystara forum in the community, but it is somewhat inactive
http://community.wizards.com/forums/103411
Indeed, I dug mine out when I got hooked on 5e. The cover art and resulting information contained within were what started by D&D journey back in 86ish. The only drawback....they were my old friend DM's books that he left me "have" i guess as he never asked for them back. Not until I contacted him to see his opinions on 5e and sent him a pick of them...he was like, hey can I have those back? 
I remember these from back in the day. During the 3.5 days, they even had excerpts on the site. I thought they were a great way to add instant flavor to any area, adventure or campaign.
DnDClassics, you say. I'll have to swing on over.
If I remember correctly, I recall one that I owned....It had something to do with vikings, and had an interesting spellcaster in it called the runecaster, if I'm not mistaken.
I don't miss the gazetteers at all - I still have all of them. But then, I am a fan of adding background and setting information with only mild amounts of crunch.
The Vikings book Meph1971 mentioned is my favorite of the 2nd edition Historical Reference series; it was the first one, they knowcked it out of the park, and never in my opinion came close again. The Runecaster also remains my favorite non-PHB class from 2nd Edition.
Several of the gazetteers were really fantastic products. While there are other campaign settings I prefer over Mystara, I think the Karameikos gazetteer may well be one of the best setting books I own. Rockhome, Alfheim, Glantri and the Shadow Elves were also excellent. There were a couple I wasn't too crazy about though: Ierendi felt kind of pointless, the attempts at making the Broken Lands (Orcs of Thar) a humorous setting resulted in a product that felt completely out of place and unusable in my opinion, and the Atruaghin Clans gazetteer was just...meh.
Great series overal though.