Do it yourself!!!!! Using these boards (and others) you can find deals equal to what a travel agent would find (if they bothered to look).
If you use a travel agent, double-check every single thing on your own!!!!!!!!! I worked in the hotel industry for years, and 99% of the check in errors came from travel agents. Everything from room requests that weren't there, to reservations for the wrong month. "Sorry... you don't get a room. We're sold out and ABC Travel booked your room for next month."
Knowing this, I still booked a cruise with a supposedly trusted travel agent (my dad had used her for business for years). Every step of the way was screwed up.
Agents sometimes have great resources, but unless it's your sister (who you know you can call at 2am), check and double-check it yourself.