hi everyone, its been awhile but i'm back

toby will be a year in mid-feb and has become... a BARKER. i dont mind as much if someone comes to the door, he thinks he hears something outside, ect. because i feel like he is barking to alert us/protect us (more than my german shep is good for lol).
the problem lies when we go somewhere... he gets so excited when its time to get out of the car he goes crazy barking. whether its petsmart, or someones house, a tball/soccer game, ect. he gets out and barks his head off, actually to the point where its very embarassing... and i dont know how to stop it. i tried the squirt bottle in the house, but he also just barked at that. not sure what to do outside of the house though, which is where the big problem lies. he barks regardless if i let him down on his leash right away, or if i pick him up. he could care less about being distracted with treats either.
he also barks when we take walks, which is also a time i would like him quiet
thanks in advance for any suggestions!