Links and recommendations are in no specific order.
Steffens shop is nice and user friendly with loads of good items,quick responses and weelky updates.
Jim is a friendly chap with a very nice shop based in the Netherlands. Good items and frequent updates.
Stefans DNA sites should be known to all collectors of EKs & KVKs by now. A huge Database with countless variants of EKs & KVKs.
This is a great website dedicated to the "italienisch-deutschen Feldzug in Afrika". Matthias has made a great job explaining the "Feldzug medaille", paperwork and much more.
Militaria Berlin is one of the leading dealers worldwide. Great items added in weekly updates.