Unless I am totally missing something, there is no way on Travelocity, or anywhere else that I know of, to request that an itinerary be priced by specific fare code. In other words, you can't punch in a roundtrip ATL-LGA-ATL itinerary on Travelocity and then ask the site to tell you the U fare and rules, L fare and rules, K fare and rules, Q fare and rules, etc., etc. You might be able to get it to tell you the lowest fare, lowest unrestricted fare, or other relatively broad categories, but you can't specify something like "Tell me the B fare ATL-LGA."

For that matter, I've never seen a site where you can even do something as simple as pull up ALL the fares for a given airline in a given market. Before these websites will tell you any fare, they always want your dates. For those that offer fares based on flexible dates, they'll tell you the lowest fare offered, but they won't tell you all the fares offered.