I tend to order from:
Midwest Supplies
Northern Brewer
Morebeer.com
I compare everything I order and go with the best deal and who has what I need. Midwest usually is where I order from. They also ship fedEx which delivers usually a day earlier than UPS and also on Saturday. This has saved me since I'm a last minute person. Plus this is a video of how every package from UPS is delivered to our door.
http://www.youtube.com/watch?v=2Q6_9A90cUk