Hi Robert,

I am going to give you a few resources I turned to when I first began citation building.

http://getlisted.org/resources/local_search_ecosystem.pdf

http://getlisted.org/resources/local-citations-by-category.aspx

http://getlisted.org/resources/local-citations-by-city.aspx

http://www.seomoz.org/directories/local

From these I create a "Top List" based on my client and their situation.

Also, I think once you dive in to this process you will find your focus shifts from "how many of these can I get my client on?!!!" to making sure the quality of your existing listings and directories is high.

All the Best,

Amber