I would like to buy a city with maps and so on, but i cant find any.
I dont want an entirely new campaign setting like Windhaven, just a city to my own campaign.
Bluffside and Freeport are very universal and can be dropped into any game setting. Both are really about equal in content but I lean more to Bluffside.
Geanavue is set in Kingdon of Kalamar, it is a LG city, very detailed. Could be used with minor work to fit ito any game setting.
If you do not mind converting some info and you have access to it, I would suggest using some of the Waterdeep material. That city has been detailed to great length.
ALthough designed for the Scarred Lands campaign setting the two city books Mithril and Hallowfaust are excellent. Mithril is the home of the 'good guys' paladins and clerics of the LG and NG dirties of the SL. But it does have its own problems in that it is pretty far away from any of its allies and the areas around the city are more or less wild country. Great detail on the city itself (and I think it wouldn't be too hard to change some names to whatever LG and NG gods fit your campaign).
Hallowfaust is a city of necromancers. But not like you have ever seen before. These necromancers, while fascinated by death and the undead, use their powers to strengthen their vity and ensure the safety of their populace. I would descibe them as True Neutral bordering on LN. The city book is very detailed with lots of flavour and interesting locales throughout the city. In addition it has some new spells and monsters the necromancers have developed. I think this one could be placed in any campaign setting that wanted a different take on necromancers.
Gee, these are very expensive!
Is that really necessary just for one single city?
But, i guess it is. I think ill go with Bluffside since its the cheapest and doesnt belong to a campaign setting. I was planning on using it in Forgotten Realms.
Or maybe Seven Cities, but since it isnt out yet...
There is always City State of the Invincible Overlord, which was reprinted fairly recently. It's $10. It would take some work to update, since it uses pre-AD&D D&D stats (or something akin to D&D), but it shouldn't be that tough. It may not be as pretty as some of the recent stuff, but it sure is detailed. Plus it's a classic.