Online Search: 

I looked across the entire country and you should too.  Prices are cheaper in the south/central United States and even if you have the boat shipped or drive to go get it you can still come out well ahead.  I posted on the forum for advice on Classifieds sites and got some good help.  While I'd like to tell you that Calfishing.com is a hotbed of boating classifieds, it's not, so here's where I wound up looking online:

www.boattrader.com
www.westernbass.com
www.bassboatcentral.com
www.craigslist.org
www.ebay.com

There are quite a few other sites out there, but those five sites seemed to carry the best listings and the most volume.  Boat Trader is particularly nice because you can run very specific searches to get a cross section of boats and evaluate pricing. 

With Craigslist, there are many sub-sites that have to be searched individually.  In other words, you can't search the SF Bay Area and Atlanta at the same time.  What you can do is go to google and search with site:craigslist.org at the beginning of your search.  You'll get expired listings, but you'll be able to search across all of their sites. 

Old Fashioned Search:

After spending a lot of time online I was frustrated by the fact that there were very few boats that met all of my criteria.  Since I was looking for a Champion I had a friend who knows Skeet contact him and see if he knew about any boats for sale.  I also emailed Mike McClelland.  I'd met Mike once at a show but a guy like Mike meets ten thousand people a year at shows, so it was pretty much a cold-call. 

Skeet didn't know of any boats, but McClelland said to give a call to the mid-west Champ rep and that he would expect my call.  I called and he knew about three boats.  Two 200 Elite's with Evinrudes and a 198 Elite with a ProXS.  These boats were not for sale online anywhere that I had searched.  I was interested in the 198 so we talked back and forth and he got me in touch with the seller.  The boat met almost all of my criteria and wound up being the one I bought. 

The lesson here is that it's worth it to contact pro-staff guys (remember my earlier comments about pro-staff guys acting like an extended sales force).  Their job is not necessarily to move used boats but moving boats in general for their brands is a good thing.  To Mike McClelland I'm just Joe Lunchbucket, but he set up a phone call and helped move a boat.  In turn, the guy I bought my boat from bought the Champion support boat from the Elite Series the year prior.  So it's all part of the boat food chain and good for the sponsoring company.  Take advantage of this, you're not putting anyone out by sending an email or making a call. 

Pricing Information:

While it would be nice to know what people out in the world are paying for used boats, that information is hard to come by.  Occasionally, a rig will go up for sale and be sold within a few days.  In those cases you can infer that the sale price was close to the offering price.  For example, during my search I saw two nice 2007 Champion 200 Elites with 225 ProXS motors go up for $32k and sell quickly.  From this, I inferred that a boat like that was selling in the $30 to $32k range as I doubt any seller would come down more than a few thousand in a week's time.  Assuming you can wait to buy a boat, it's worth it to watch this sort of information to get a sense for what a fair price is.

It doesn't hurt to call and get a few prices on new boats either.  I called on a new 2008 Champion 198CX with a 225 ProXS and was quoted $37k + fees.  This was a pretty stripped down boat with just the basic options.  Pricing information like that is useful though because it helps build a sense for what a fair price is on a used rig. 

Blue Book:

The Blue Book of boats is called NADA.  I would suggest that bass boat prices are much harder to estimate than car prices due to the variation in individual boats and the low total number of boats on the market.  But it's a start:

www.nada.com