There are many sites on the 'net that will teach someone how to do Reiki. A lot are pay sites, some purport to be 'free' but are going to try to charge you money before you're done, and then there are truly free ones who have your interest in mind, not their wallet. The three listed below are the ones I'd recommend. I'll post in a day or so with links to groups that will offer free attunements and lots more info along with real people who will respond kindly to questions about Reiki. The fourth site listed is for much good info but not Reiki manuals.
This first link is to a site owned by Peggy Jentoft, and the one I like most. She's just recently re-written her Reiki manuals and I think the new versions are great! There are other parts of the site with lots of info on healing through other forms, including crystal.
http://solarraven.com/reikisplash.html
This site was owned by Vincent Amador, and contains his manuals. Lots of good info in the articles section too.
http://web.archive.org/web/20020601113128/angelreiki.nu/
The next site has a huge amount of Reiki info, including the most detailed history I've seen yet. You can access the Reiki Pages from the navigation bar on the left of the main page.
http://www.aetw.org
The next link is to a page with some very interesting essays on Reiki, written by some of the best known names in western Reiki. I'd suggest reading all of 'em. Scroll down toward the bottom of the page to find 'em. Be sure to check out the link at the bottom for 'related articles.'
http://www.realmagick.com/articles/74/2274.html
Hope this helps everyone.
tomas