Ottawa airport is not far from downtown and the cab fare is affordable. You can also take the bus from the airport to downtown: it takes 20 minutes and it is very cheap. Ottawa has a very good transport system. The bus will take you anywhere, but all recommended hotels are downtown which means you will be able to walk to the university.
The Faculty of Arts is on 70 Laurier Avenue East, 5 minutes walk from the Novotel and other downtown hotels.
It may be that you do not find a cheap direct flight to Ottawa (especially if you are coming from Europe), but to Montreal. Once at Montreal Airport, you can either take a short flight to Ottawa or the bus (it takes two hours on the bus). The bus will take you downtown in Ottawa, very close to the University in fact where most of the hotels are.