Hi. I came from Buenos Aires for first time. I hired a local guide who also was a tango dancer. She booked me a tango show wich was amazing but it is a touristic place. Is a must to do !!!! but is completely different to what I have seen the next day. She brought me to a dance hall to watch local people dancing and it was boring for me (as I cannot dance anything!) but it was different and lovely.
If you know how to dance it will be better but is difficult to understand where to go as she always asked me wich day all the time as she told me that depend on the day is different, except for tango shows.
I went to a tango show wich I don´t remember the name now , I will and write back, but it was first class with wonderful food and wine. Dancers were amazing!
You can read this post that was written by her with some videos about tango: