Creating List for Listsource to find Motivated sellers rookie

[Teonia Riley]

I want to create a cheap list since im on a budget, but I also dont want that to hinder me from learning something of my interest. I want to try to keep the list under $100, but I don't quite understand what to look for in creating the list that will still be worth value to send out postcards. 

If anyone can guide me to some clarification, im definitely willing to learn, listen, and perfect my knowledge with wholesaling. 

thanks everyone.