Hello Blake! Welcome to the Forums!! Any time you spend here cruising the main portal page will give you ideas of how to proceed.
Craigslist has gotten some mention recently. I would suggest getting ideas of content on the Classifieds
here. Other classifieds are also at VAC
even has a classifieds section although I can't say much about that. What I can say is 'watch out' for ebay -- just read any ebay thread here and it usually pertains to hard luck trailers or buyers getting burned -- especially frauds that surround any presumed newer units! The '75th' in your thread title suggests you'd be interested in a much newer unit since the 2006 models were the 75th anniversary (2007s have been out for something over a month now). There probably isn't much turnover for 'used' in that category. Bambi size of anything is in high demand.
There are a lot of options here, there and elsewhere. Hang around, ask & listen, and you'll be happy to buy when you've studied the field.