You can download a sound file or create one yourself. It has to be in mp3 or m4a format. Using a file manager, place the file in the "notifications" folder on your device. Then when you go into your settings to change the notification sound, you'll see your file in the list. Simply select it...
An AT&T sim will not work in a Verizon phone without it being unlocked and reprogrammed for AT&T. Verizon uses CDMA whereas AT&T uses GSM. You may be able to take it somewhere and have it unlocked. You need to go to AT&T's website and check the IMEI to see if the phone is compatible...
Download a file manager if you don't already have one. Go into the settings of the file manager and make sure its set to show hidden files. Then look in your folders for pics
I don't know where you live, but there is a Radio Shack (yes, there's still some) inside of the Gateway Travel Plaza in Breezewood, PA. Maybe if you call them, they might take an order over the phone. I bought one there a couple of months ago.
Look in your Bluetooth settings and see if its showing paired with media audio or just calls. Also, you may have to configure the car's audio settings.