These Macleans is a Canadian newsmagazine that carries out the most widely read annual rankings of Canadian universities (the 2012 rankings should be out shortly). They consist of an entire magazine, which is summarized here:
Maclean’s 2011 University Rankings – - Macleans On Campus
They break out the "Primarily Undergraduate" schools, which would include your "liberal arts" colleges.
Like any ranking system, they apply subjective weights to various criteria, which may not coincide with your/her preferences... with this in mind, they have this clever tool:
RANKINGS TOOL – - Macleans On Campus
PM me your address if you are interested, and I will try to mail you a copy of the 2012 rankings issue when it comes out.