Hi Justin--I want to take this opportunity to express my appreciation in working with you.  It is refreshing to have someone complete a task they were hired for without supervision.  I must say that you have been professional and friendly in working with us.  I am very glad we chose to hire you for our project over some other groups we were considering.  

I have had mostly negative and difficult experiences in working with web designers/developers.  This has been my first positive experience in such field.

Again, thank you for delivering the services you promised in a professional and friendly manner with a reasonable rate.  I will recommend you to anyone whom I think will benefit from your services.

Best regards,

Amir