Nothing leads to fluency in a language like studying it in a country where the language is spoken. If you prefer a package deal that includes classes and housing, search for a formal program. StudyAbroad.com, for example, lists overseas language programs on its site (click on “Program Type,” then “Intensive Language”). Prices vary widely, but you can expect to spend at least a few hundred dollars per week on instruction and lodging, potentially with a host family.
Living abroad but forgoing the structure of a program may save you money. For example, Barbara Pagano, of YourSabbatical, who spent several weeks studying Spanish in Nicaragua, researched schools while at home, then visited a handful of them after she arrived in Nicaragua. She ended up hiring an instructor in Granada, who charged $5 per hour, and she lived in rentals during her stay.
If you can’t leave home, consider enlisting a native speaker to practice with you. Find someone who wants to sharpen his or her English and be both a student and teacher. At www.language-exchanges.org, you can search for a partner to chat with you using Skype.