Altın beşik
Altın yaş olmak
Altın okka etmek
Ar belası
------------- I really don't know about these 4 above here.
Arada kaynamak; get lost in the shuffle, or to pass unnoticed
Otobüste arada kaynadım. (this sentence means that the person didn't pay for the bus, he/she pass unnoticed)
Aramakla bulunmaz; something very rare (literally it mean; (something) even though you search for it. you can't find it)
Onu çok eskiden almıştım, artık arasanda bulamazsın. [I bought it long time ago, you can't find it even though you search for it] (the person wants to tell don't waste your time for searching it.)
Hope I didn't make you confused, because these are idioms a little hard to explain ^^