Hmm... you knew you'd wind up getting more and more questions, didn't you?
Is your phrase Irish gaelic or Scottish gaelic? (there are differences). That may affect the way your phrase appears. The alphabet / numerals are the same as the ones used in english, so yeah, you're in good shape as far as that goes. You'll want to pick a "font" or typeface that will go well with any accents that are put above the letters.
Check out
http://encyclopedia.thefreedictionar...lic%20language
for some information on Irish and Scottish gaelic.
As for fonts, check out Gaeilge on this website:
http://babel.uoregon.edu/yamada/fonts/celtic.html
I downloaded it for free for macintosh (likely windows is free too, if that's your bag.) Looks pretty good. Of course, all the letters are there for the 'english' language -- you'll only need those which your phrase requires.
Let us know how it works out! (and post pictures
)