ORIGINAL: ark3
If you do decide to go with a collar, I would suggest a citranella collar. I find they are more effective than shock collars and more humane. I know several people who have had a tremendous amount of luck with them.
I am one of those people. [

] Sashka would bark for hours when left alone. We started using the citranella collar when we were home at first just so we saw her reaction to it. I only have to use it a couple of times a year now. I usually only leave it on one day and then for the next couple of she wears it but it is off. She knows that barking (for a long time) is no fun. Now I just show it to her. LOL