Florida's five largest companies (thank you to mtbopfuyn for finding the source: http://www.businessflorida.com/leaders/pub.asp ) are listed below. There is a lot more here for the average person to be able to boycott.
1 AutoNation Inc. (278 dealership locations representing 355 new vehicle franchises across 17 states) http://corp.autonation.com/contact.asp
2 Tech Data Corp. (Computer products) http://www.techdata.com/content/visitor/abouttd/NS_Feedback.aspx
3 Office Depot Inc. (Office products retail and distribution) http://www.officedepot.com/customerservice/input.do;jsessionid=0000FDFSYWJJ4CSEAYHREGTSX0Q:uk1sst7b
4 Winn-Dixie Stores Inc. (Grocery) http://www.winndixie.com/comments/main.asp
5 FPL Group Inc. (Energy provider in 26 states) http://www.fplgroup.com/contact/contents/contact_us.shtml
The only one of those that I have used is Office Depot, and rarely.
You left off Tropicana of Bradenton.