Can anyone tell me what the best hair dryer/diffuser combo would be for long (lower back) curly hair??

Answer 1

Use professional blo dryers, they have a longer life, more power (go for 1600+ watts), and always come with a diffuser and nozzle.
Ask your local hairdresser to order it in for you, she will be able to get it for a slightly lower price than if you were to order it in yourself from somewhere.

Answer 2

Anything BUT conair
Conair has horrible products, stay away.

Probably the best product you would want to look for is one where the diffuser detaches from the hair dryer. Ask your stylist? They may even give you a discount if you smile pretty.