There are many types of desktop testing tools which you can learn about through websites that specialise in them. If you have a software development requirement which would definitely include the process of quality assurance then you will want to investigate about desktop testing tools which would simplify the whole process for you.
If however you cannot take the entire responsibility of taking care of everything in house then maybe you might want to outsource the quality assurance process to software development specialist companies that can take care of the job better for you. You will be expected to carry effective research out so that you can find the right company that you could be working with.
It is also essential that you understand what quality assurance is all about so that you can then proceed in the right direction when identifying the right company or the right set of desktop testing tools that you could be working with. By not knowing what you should be looking for, the whole process would be daunting and you will lack in accuracy when trying to figure things out.
So, the first thing before you go ahead and start researching about desktop testing tools for you to do would be to know your requirements.