In adultery cases, it is fairly common for a spouse to attempt to gather information, either directly or through use of a private detective. I do not recommend a spouse attempted to track the other spouse themselves. It is far too easy to run afoul of the law in checking a spouse's emails, tracking a vehicle, taking video, etc. Sure, it is much cheaper than hiring a professional, but you are taking a huge risk. (The same could be said of people who represent themselves in the divorce).