I use "United States-Gaeilge" keyboard mapping in Win7 (x64), to do the punc all I have to do is type:
/+consonant
eg:
/b = ḃ
/c = ċ
/d = ḋ
/f = ḟ
/g = ġ
/m = ṁ
/s = ṡ
/t = ṫ
Accents for Gàidhlig:
`e = è (etc.
Tironian et (== agus)
\& = ⁊
"Ceol ⁊ craic"
http://mearchlar.tripod.com/ based around the "US International" keyboard which is handy anyways as it has keymappings for umlaut's etc. As my work laptop has a US keyboard layout (" swapped with @) it was easy enough for me to switch from standard Irish keyboard to US one.