helsinki is awesome... very small though.. expect a super packed house for that show!
as for hotel... it's ottawa.. everything is cheap compared to Toronto.
try ARC.. nice boutique hotel about a 5 minute walk from helsinki. rooms run around $130 a night to start.
also les suites.. also less the 5 minute from helsinki.. across from the old atomic space.. a little bit more expensive but you get HUGE suites.. like $175 you can get a massive 2 bedroom suite with laundry, full kitchen, living room, dining room and all that.
or you can go with the usuals like holiday in, best western, days inn etc... they'll run you like $100 a night max.
It's bordering on a BnB except that noone cares when/where you go and at what time. Plus they make the best goddamn European styles breakfast complete with Bircher Muesli, hunks of good cheese and dark rye bread. And yummy coffee.