As the page grows and peoples want to contact me, I added this page with different methods to contact me:

Best way is via IRC as user eche|on on the #i2p channel.

Second best way is direct via email.
As someone pointed out, I needed to add my PGP key: PGP-Key-ID: 0x4A9B1723
Hence that key is for my other email address l.schimmer@cgv.tugraz.at ! Currently I do not have a I2Pmail PGP key only setup.

And from now on I got a I2P messenger ID:
sg4QbkAbx7cU9kJUxLf5RCegRbj2wMo8TyDewTJ1SGMEkrjH7mK~1clHtzT3qVC2hbxhre4e2XG7a-pmtI5Xm0fErH9H1r3PC1xzx311MAgcIAEOMxFyFvG8tyyg4CqdglMerdwbajQtC0TnMMgeP-TsEW48kKN6JIH7YgrcJVlU0AQ8-PefcSDufVucnH9BQGEMuj28cQp7vRrQO8WkmU9XmzygTcH7LV~zf-l6l04iQ~uiLmuCdvb~dfTbfyjiAxxSoDVMg645ZK7ias0Zq8dn7VdBifISz4gDyk7oJEGgC36vrRJZsigm2ZxFXkfW3TjRMDqi3b4rCztfazqgf4Y2nUSw5EdMKiPnn25Re~oAAAs0tO-RVzKr-OXKojxr8NKKKXAFCibf5NReIWSgBNAzg0hZ~-zPe7T3-KL4qJLGACBdDY7MFLM~SV2PLdfKh0H8b0EOSK-QJaVPlJwPeZc8BTUMWCQN7leiCSdsk5TQDzgOkpbCXgXLHzpbcTZtAAAA

Copy that long destination ID as one line in your I2P messenger to add me as a contact.