Assuming by highest likelihood that you're German, my reading of the relevant section of the criminal code suggest that it's OK for you to debate in Internet fora:

(3) Whosoever publicly or in a meeting approves of, denies or downplays an act committed under the rule of National Socialism of the kind indicated insection 6 (1) of the Code of International Criminal Law, in a manner capable of disturbing the public peace shall be liable to imprisonment of not more than five years or a fine.

(4) Whosoever publicly or in a meeting disturbs the public peace in a manner that violates the dignity of the victims by approving of, glorifying, or justifying National Socialist rule of arbitrary force shall be liable to imprisonment of not more than three years or a fine.

Unless it can be argued that you'd be "disturbing the public peace". But as I understand it, in Germany (and France) it's legal to visit Stormfront, you just cannot promote it.