I've been working on a list, in addition to the citrus industry and major tourist attractions.
Here it is so far:
All Chem (chemical raw materials)
http://www.allchem.com/overview/overview.htm
Applied Digital
http://www.adsx.com/aboutadsx/corporate.html
Arthrex (tools and products for arthroscopic surgery)
http://www.arthrex.com
Audio Visual Innovations (audiovisual projectors and displays)
http://www.aviinc.com/companyinfo/contact-location.asp
Beasley Broadcast Group (radio stations in Boston, N.C., Philadelphia, Fl., Ga.)
http://www.bbgi.com/
Certegy (card services)
http://www.certegy.com/
CSX (refrigerated transport)
http://refrigeratedtrans.com/mag/transportation_csx_corp_moves/
DHL Express Americas Headquarters (shipping)
http://www.dhl-usa.com/CustServ/ContactUs.asp?nav=CustomerService/ContactUs
Ductbusters (HVAC)
http://www.ductbusters.com/tombio.htm
Dyadic Group (biotechnology)
http://www.dyadic-group.com/wt/dyad/pr_1090430529
Florida Chemical (d-limonene natural pesticide, citrus oils and terpenes)
http://www.floridachemical.com/Default.htm
Harris (network support)
http://www.networksupport.harris.com/products/netboss/
Kforce (professional staffing)
http://www.kforce.com/Kforce/corporate/me.get?WEB.WEBSECTIONS.show&KFORCE_118
Logistic Services Intl. (military logistics)
http://www.lsijax.com/corpinfo/about_lsi.htm
MPS Group (provider of staffing, consulting, and solutions in the disciplines of information technology, finance and accounting, law, engineering, and healthcare)
http://www.mpsgroup.com/
The New Piper Aircraft, Inc. (airplane manufacturer)
http://www.aerospaceonline.com/storefronts/newpiper.html
NovaVision (vision therapy and neuroscience)
http://www.novavisiontherapy.com/english/about/index.asp
Paradyne (telecommunications equipment)
http://www.paradyne.com/company/
Red Vector (online education for professionals in the engineering, architectural, interior design, construction, land surveying, building inspection and landscape architecture industries)
http://www.redvector.com
Rotary Aviation (aviation and motor products)
http://www.rotaryaviation.com/
Webcast1 (website design)
http://www.webcast1.com/company_profile.html
Sabine (professional audio equipment)
http://www.sabine.com/sabine-inc.htm
Speedling (plants)
http://www.speedling.com/about/
Check out the link for Florida's big businesses.
http://www.businessflorida.com/leaders/pub.asp