Learn German in Germany
There is nothing better for improving your language skills than studying the language where it is actually spoken. And few organisations are as serious about their work of spreading the German language and an appreciation of German culture than the Goethe Institute (www.goethe.de.)
Goethe used to be heavily subsidised by the German government, but in these days of austerity that is no longer the case. I have taken courses at Goethe in Montreal and several years ago spent two weeks in Berlin on a langauge and culture program
. The latter was a good experience, though I could have worked harder at immersing myself in the culture by reading German, watching German television etc. While the course itself was valuable, the best part was being able to spend two weeks in Berlin, one of my favourite cities, at a reasonable cost. I had a nice room in an apartment building very close to Ka DeWe, the wonderful Berlin department store, for 15 euros per night, and I shared the apartment with a pleasant young Russian girl who was studying at a different school..
Goethe offers a variety of programs to suit virutally any demand for the language, and you can study in many different cities. The Berlin location is still available, but without room, and a language and culture program costs 785 euros for two weeks. In a smaller place such as Schwaebisch Hall, a two week longauge only course with a single room costs just a little more, at 805 euros.
The courses aren't cheap, but costs compare favourably with spending time on your own, trying to pick up the language just by travelling. A course gives you a ready-made social circle as well as instruction, so it is a good option for the lone traveller. And don't worry if you are beyond the usual student age, since many of your classmates will probably also be older, possibly even retired.