To check broadband, fibre or ADSL availability in France take a look at any of these web sites (you will need the commune post code or existing phone number):
ORANGE (France Telecom)
DSL Valley ADSL
Keep in mind that the speeds quoted in these results are estimated and not contractual. Broadband speeds may vary within the same commune and postcode. If in doubt, it is advisable to consult with a professional before acting on this information.