Language learners sometimes talk about tandem partners for practice. Tandem language learning is a model in which each native speaker of a language teaches the other speaker his/her native tongue through informal conversation. Ideally, each native language is practiced with equal weight (50-50). The one-on-one practice is intended to be more interactive than traditional classroom exercises. Furthermore, the authentic relationship with a native speaker is highly motivating.
The major downside is that such intensive oral practice requires a minimum background of a year or two of basic vocabulary, grammar, pronunciation, etc. Additionally, finding a tandem partner may be difficult for some languages! Native speakers of English, for instance, may easily find a tandem partner for any given language that they want to learn. In contrast, a native speaker of a much less commonly spoken language might have a much more difficult time finding a partner. The supply and demand are likely to be unbalanced.
An extensive bibliography regarding tandem language learning is available at the University of Ruhr’s website (last updated 2007).
E-tandem partners are widely available online. One particular resource is the University of Ruhr’s online database.
Of course, you may always refer to the Learn a Language page at the Literatures and Languages Library for independent language learning.