Mel suggested Effie and I could put some recipes here so they can be found easily. Non Greeks are totally welcome to share their recipes for Greek foods or ask for recipes and we'd be glad to help.
To start with, my tzatziki:
Find some strained Greek yoghurt,whatever is available in your country. Not low fat and make sure it's not blueberry flavoured or something (yuck)
Crush 2-3 cloves of garlic and stir them in the yoghurt.
Grate an unpeeled cucumber on a plate and wring the excess moisture with your hands. Afterwards stir it in the yoghurt.
Add some red wine vinegar (not a lot, around a tablespoon)
And if you want, you can also stir in a little olive oil.
Sprinkle dill on top and you're ready