WOW! That's a lot of useful information and great tips! Thanks a lot, guys.
See, jurek, I didn't even think of the difference between a bird's call as opposed to a bird's song (I hope, no nightingale is seeing this. :p). Thanks for describing the differences andthings in common. I find this very helpful. I'm just such a beginner.
Henning, a ton of great information, danke dir! I'll check out the German forums for sure and you're right: I'm already checking out birds songs here at home. What I am doing currently: I am trying to take pictures of all the birds around my home, not considering quality but identifying the bird. Then I look up the sounds. Green finches and golden finches so far.
It probably doesn't help that I'm primarily more a visual person rather than an auditive one, so the sonagramm sounds like a book that's closed to me. Nevertheless, from all the suggestions here, I will find the method that works for me. Thanks a bunch, everybody!
PS: One thing I have learnt from bird watching is patience and I guess, this is what is required here as well. Just with myself