If you are investigating flying in, make sure to look at Aspen- only 35 miles from Glenwood Springs, and there is public transit available- the Roaring Fork Transit Authority has a whole network of routes connecting Aspen and Glenwood Springs-http://www.rfta.com/valley.html
Aspen(or Fat City) has, counter-intuitively, really good fares- at least from Chicago. I saw winter flights last year for as low as $220 r/t. At the moment, Chicago Midway-Aspen would be the cheapest way for me to get to Convention- $50-$100 cheaper than any of the neighboring airports.
While I'm planning on carpooling from here, Amtrak is an attractive option- $330 r/t from Chicago at the moment. It is a 24 hour train trip- but the driving time is 19 hours.