Highly recommended service
I too had not to great an experience with Travelocity customer service. So, I tried Expedia.
I have used them for at least 5 trips now and have been VERY satisfied. I like the fact you can use the .NET passport (yes... some companies are still doing that) so I don't have to maintain yet another user/pwd combo.
And the couple of times I have needed changes, customer service has been excellent! Hope they work out as well for you - highly recommended.