Groups and dancing (London)

Hi,

I am new to London and internations was recommended to me. I am looking for places to dance; salsa, samba, tango, bachata, swing and zouk.

I see that there are activity groups that may serve my purpose, but I am just a basic member, so cannot view them. I am not sure if I want to become an albatross, so please can you tell me what the advantages are and if it is just a place for discussion or somewhere with real activities?

Thanks in advance,
Ana