Reiki Masters:
I started with Reiki in Oct. 2008. I have had attunements from many Reiki Masters in that time. Some attunements via Google/Yahoo/Ning Groups etc. I highly recommend the following, they are amazing Reiki Teachers.
School of Living Reiki Therapies
Grand Master Jay Burrell
I highly recommend Master Jay Burrell, he provides continuous support, is always available if I have a query etc. I have had most of my attunements through Jay. The attunement, manuals and certificates are always excellent. His attunements are always at an affordable price for anyone.
Free Etheral Crystals Attunements
Master Susan Peck
Free Attunements
Master Stefan Kammerhofer
One Healing Academy
Master Stephen Lovering
Crystal Moon Star's Store
Master Karen Tritton
Masters Healing Light Academy
Dr. Rev. Tracey Loper
For FREE attunements etc you can also join Yahoo/Google groups. There are many Reiki based groups where you can add your details to the database for attunements. Just do a group search for 'Reiki Attunements'.