Where can I purchase a used aliner the smallest one

In addition to what has already been mentioned, you can always look at the Aliner's Owners Club classified For Sale. Occasionally used Aliners, Chalets, etc. show up on RV Trader website.

Your best bet is to watch Craigslist. That's how I found mine the other day. I use searchtempest dot com to conduct the CL search if I want to cover more cities than my nearest one; it lets you set how many miles radius you want to search.

Sort of like Cars.com or Autotrader.com, you can check out http://www.rvtrader.com/ for possibilities. Also, you can use global Craigslist search engines such as http://www.onecraigs.com/ or just your regional Craigslist.

a local dealer has them starting at $9,995. don't know how much less a used one would cost but if only a thou or so, think I'd rather buy a new one with warranty, etc.
bumpy