American Demographics [1] Always fascinating.

DMA Guidelines Quick Reference page [2]

Newsletter Biz: the Newsletter on Newsletters [3]

Survey Monkey [4] Do-it-yourself market research.

Constant Contact [5] Online email newsletter management service.

BtoB Magazine Online [6]A good resource for everything B2B-related

Chief Marketer [7] Lots of useful information and opinion.

Marketing Sherpa [8] A great source of marketing advice.

eRSVP [9] Online event registration management.

Brazen Careerist, the blog [10]

Ducks in a Flow [11] A client's blog on marketing professional services.