I had a friend who tried the shock collar for a barking problem (it's not that bad, really it's not - do it on your arm, it's just a little tickle)... thing with them is, they're designed to shut off after a certain number of jolts, and her dog just figured out that if it KEPT barking, the zapping would stop, too.
Another friend tried the citronela spray collar, but discovered the dog actually liked it
You can go through a lot of money trying different $80-$100 "solutions" to find something that works, and it may only work temporarily... finding the root of the barking and addressing that is likely to be the better long-term fix, and will probably be cheaper overall.