I learned French when I was 21. It took me a long time to improve my pronunciation, which was one of the motivations for founding Chuala.com.
Chuala is basically a "Wikipedia for pronunciation" where native language speakers record words and sentences in their native language to help others learn the language.
Chuala has loop and "record and compare" tools to help language learners practice pronunciation. We are looking for people to record content and help us build up a really useful free tool.
We want to build a truly useful pronunciation database with good learning tools. We are looking for people to record in their native language and to give us feedback about their needs.