I would start doing research on which one you specifically want to get (this website is an excellent resource for that) and once you find a mod you would like to get, if its a rare one its going to take some hunting but they certainly aren't impossible to find. For example, I had been wanting a vanilla mod for a little while and they are pretty tough to find online, went into my local vape shop when I got back to my university for the semester and, to my surprise, they had two of them sitting in one of their display cases. Sometimes patience is all it takes