There are a number of Music Programmes around where you compose on screen using manuscript (others may point you in their direction) however I prefer to use ABC.
Go here to find out about it.Lesession

In essence a string of ABC text is compiled in Notepad and then put through a converter programme such as this here Tune-O-Tron to produce the dots.
Below is The Kesh Jig as string of ABC text. Copy this from, X:1 to :|, and paste it into the tune-o-tron and you get dots!! Voila!
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X:1
T:Kesh Jig
T:(Kerrigan's Jig)
M:6/8
L:1/8
K:G
"D"D|!fermata!"G"G3GAB|"D7"ABA ABd|"G"edd gdd|"Em"edB "D7"dBA|!fermata!"G"G3GAB|
"D7"ABA ABd|"G"edd gdB|"D7"AGF"G"G2:|"D7"A|!fermata!"Bm"B3"G"dBd|"Em"ege "G"dBG|!fermata!"G"B3dBG|
"D7"ABA AGA|"G"BAB dBd|"Em"ege "G"dBd|"G"gfg "D7"aga|"G"bgfg2:|
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regards
Jake