I'm considering advertising in general national magazines. (So far we've only advertised in specialty magazines for our industry.)
I'm wondering what the range of rates is (for say, a 1/6 page color ad) per 1M (1,000) primary (not "pass along") readers.
Many magazines have their media kits online.
Time Magazine: http://www.timemediakit.com/ Time's US national rates: http://www.timemediakit.com/us/rates-specs/national.html For instance, a 1/3 page b&w ad that runs 48x in a contract year will run you $99,300 per insertion or $4,766,400 for the full contract.
Links to the media kit can usually be found in the footer of the mag's main site. Some kits don't include prices, but many do.