Inputting characters with specialist diacritic marks in emacs

[mikew2801]

Hello,

I am a linguist who works particularly with Indic languages. I am trying to do 
most of my work in emacs, but I am having problems using characters with 
diacritic marks (for instance ā, ī and so on) which are commonly used to 
transliterate old Indic languages such as Sanskrit and Pali.

My makeshift solution is to use the "global-set-key" function to bind 
individual characters to keys, e.g.,

(global-set-key (kbd "C-c y") (lambda () (interactive) (insert "ñ")))
(global-set-key (kbd "C-c t") (lambda () (interactive) (insert "ṭ")))
(global-set-key (kbd "C-c d") (lambda () (interactive) (insert "ḍ")))

This is not ideal since it's quite difficult to type these bindings. In Linux I 
use Ibus mappings which involve double-tapping a similar key (e.g., when I type 
"a-a" I get "ā", when I type "i-i" I get "ī" and so on.

The question is - is there a way to make similar key-bindings in Emacs? Sublime 
facilitates this, but I'd rather stay in emacs and emacs 24 refuses to work 
with Ibus (I've tried other help forums on Ibus/emacs to no avail).

Any ideas/comments would most appreciated! As you can tell I'm very new to 
emacs.

Mike