Partial answer in the US:
http://www.flyertalk.com/forum/Forum50/HTML/013556.html
Two warnings:
consoldator ticket is hardly if ever upgradeable. Second you are lucky if you'll accrue miles on a consolidator ticket.
Buying a cheap product you can't expect much added value from the airline, such as FF miles or u/g.
So you really can be assisted by any of your friendly neighbrhood travel agents for a cheap ticket.