If you don't know this, try reaching out to others. One great site to use for connecting with others is GenesReunited. This is by far the best place to connect with others that are researching your same ancestors. Upload your Gedcom and let the smart match filters connect you with distant cousins around the world. The subscription for the year is £20.20 ($32 usd). You will only need the basic membership so that you can be matched up with others and discover where your ancestors lived.
Another way to try and learn where in Scotland your ancestors were from is FamilySearch. Check the already submitted genealogies, Making sure that you always check the actual records for yourself to make sure you are connecting yourself to the correct family.
Once you have found your ancestors, you are ready to move on to the website where you can actually view the documents. The ScotlandsPeople website. This is the website for the records of the General Registrar's Office (GRO). Their website is the repository for all official documents: birth, marriage, death, census, wills and testaments.
This website is the ONLY place where you can see images of original documents. The other websites only provide indices or transcriptions, which limits the amount of information you can get regarding your Scottish ancestors.
Happy Connecting!