Not really a list, and just for at least partially sequenced bacteria: http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=2

Be careful: some of those are just proposed, and on some of them I have serious doubts.

The "definitive" list ist the "List of Prokaryotic names with Standing in Nomenclature":

http://www.bacterio.net/-allnames.html

It contains all validly published species and is updated regularly.

agree with Guilio Dalla Riva. you can search it on NCBI site

Thanks for you answers. I'm looking for a downloadable table. It seems neither NCBI or bacterio offer this possibility.

try :

The Global Biodiversity Information Facility (GBIF) at : http://www.gbif.org/

and Catalogue of Life at : http://www.catalogueoflife.org/

these contain valid data.