Looking for resources to find names for a campaign, preferably sorted by language/culture. I like BehindTheName, but am wondering if there are other favorites that people always use.
The Onamastikon is superb. Tons of real world historical name lists.
If you can live with names that simply have the "feel" of a particular culture (same morphemes, etc.), there are good ones at:
Chris Pound's Name Generation Page http://www.ruf.rice.edu/~pound/
squid.org Random Name Generator http://www.squid.org/rpg-random-generator
If you want names that are actually used in real world cultures, your best bet may be one of the infinitude of "baby name" websites.
The Story Games Names Project† contains more than 100 lists for different cultures and genres, each one containing at least 20 male, 20 female, and 20 surnames. Many of the lists contain more than that.
The project resulted in a published book as well as the online index of names in PDF and text formats, released under a Creative Commons license. The book is a great offline reference at the table, but the online version is a useful reference accessible from anywhere there's a browser.
†The book/project is confusingly named. It's not a project of names just for story-games, but rather a names project that was organised on story-games.com.
I've long been a fan of the Random Name Generators at Rinkworks. There's your basic stuff, plus some more esoteric types of name generation (like the Fake Pokemon Names) and even an advance name generator so you can set up custom random name creation. Pretty sweet.
SCA name research sites are a BIG source...
Laurel Sovereign At Arms (http://heraldry.sca.org/laurel/names.html)handles all SCA name registry for the Society for Creative Anachronism, and the sites linked to are all fairly well documented, most to historical publication standards.
Don't bother asking for help here, tho'. The resources and time are dedicated to SCA heraldry, and it's a lot of work for the senior heralds, and those senior heralds are busy.
Acadamy of St. Gabriel (http://www.s-gabriel.org/) is pretty much the first source I turn to as an SCA herald; anything they use is documented to SCA standards or better, so I seldom have to go much afield from there.
A word of warning, tho'... contacting them for help with character names is bad form, but using their online resources isn't. They're focused on the SCA and other similar groups, like Acre or Corinthia.
Both, however, are excellent also for researching realistic heraldry.
Both also have links to a number of other sources.