Deskpass - Tampa Coworking & Shared Space Membership
IdeaField is no longer operating a coworking space, but there are many resources in Tampa Bay that cater to the tech and freelance community.
The Tampa Bay Innovation Center (f.k.a. StarTec) operates the Tech Garage in downtown St. Pete.
CoWork Tampa has a facility with both open seating coworking and dedicated office space for rent.
WaVE Coworking is in downtown Tampa, look for their new location in the Fall of '15.
If none of these work for you, you can still find ad-hoc coworking around Tampa Bay at places such as:
Buddy Brew Coffee on Kennedy
The Bunker in Ybor City
Cafe Hey in Tampa Heights