Hi Mayborn
Aari work is also called tambour work. It was extremely popular in the 18 & early 19th Centuries in England.
I've never actually done any tambour work myself, but will start doing some more research for an article on it.
There are many different ways to transfer patterns to fabric - just checked. I thought I had put up an article on this, but it's not there. I have definately written one, so I'll dig it out and make sure it's all up to date and post it.
Welcome to Embroidery, Mayborn. It's a very rewarding hobby - and India has some beautiful forms (especially shisha work).