Dealing with Neighbors barking dogs

I know this may be a sore subject or may upset some, but Im at wits end with my neighbors 2 barking dogs. This has been an issue for over a year now and nothing is being done to stop it. I truly believe my neighbors get some sick thrill out of upsetting us.
These dogs bark at anything and everything! Birds, kids, rabbits, wind, etc..... I have quit working in my gardens on that side of the house because they will bark constantly. We live out in the country so laws are pretty relaxed. We have called the law several times in the past year but not much changes.
We have been looking online at the ultrasonic anti barking devices but before we drop that kind of money on someone else's dogs we first want to make sure they will work. I would like to hear from someone that has had some kind of experience with these products or if there is another product I would love to hear about it!
Thank you for any help!