Here (French). There's a very good English language site giving much background about the procedures and work of the assemblee here.
There is a "parliamentary channel" - LCP - http://www.lcp.fr/ (which is available also as an iPad App; iPhone App; and an Android App).
The next elections - once again run over two rounds - will take place on the 10th and 17th June. The country is divided into 577 districts ('circonscriptions'),
The law relating to the elections can be found in the Code electoral. The version which is due to be in force for the legislative elections in June can be accessed here.
If you are like me - obsessed by electoral statistics - then you can delight in the results of recent previous elections which can be accessed here.