Get ScrapeBox -- http://www.scrapebox.com
The social account scraper allows you to load in a list of sites and it will scrape the social account urls from those urls you load in. It can even deep crawl the site based on keywords you enter to look further if the profile urls are not on the pages you load in.
At the time of launch it scrapes profiles for
Facebook
Twitter
Linkedin
Pinterest
Google +
Then you can export these urls and use them for many different purposes.