Back to the original question of travel agent vs. web sites. My preference is to research myself and then I present my research to my agent with a challenge to "beat that!" My agent can usually beat it but certainly always matches it. In the end, I always have my agent book and ticket it for me as an agent can offer certain perks that I have not been able to get from a web site. They are:
1) Free travel Insurance
2) A few discount coupons here and there
3) On my HKG flights I always get free airport/Downtown ground transfers.
4) On multiple legs, I can get all flights on one booking. This has been especially useful when my agent ticketed seventeen flights for latinpass on one booking. This technically means that a flight delay will also make changing reservations for next flight a lot easier.
5) Plus I can help another person make a living.
6) Whenever I have a special request, my agent really tries hard to secure it for me. IE: My son had his 11th Birthday while flying across the pacific on the 17 hour HKG-YYZ flight and we were able to get a birthday cake on board (no candles though).

Go with an agent if you can but especially so if you travel a lot and need that extra hand to ticket and "watch out" for your best interests. Also, a lot easier to get refunds if needed.