I remember a cab from downtown to the airport being about $35, unless they jacked up some new flat rate.

There's a few buses you can take besides the city bus, which would probably only stand a chance of taking your bikes if they're still boxed (don't take my word though). Or, like most airports in major cities, there must be a $10-20 shuttle you can take into downtown.

If you're cycling then you've got to bike the waterfront--and take your bikes onto the islands, which are car-free. Use Google maps/satellite hybrid view to get an idea of where the paths, beaches and green spaces are. The eastern-most point to bike to would be Cherry Beach, a great place to relax for a while after a ride. Lots of windsurfers and sailers on that side, and the water looks great from there. The western-most point to bike to would be a few km beyond Exhibition (an area that includes BMO field), where some wetlands and a park sit adjacent to some highrise apartment buildings. You'll cross a white suspension bridge right before this area. The beach that you'll be biking by for part of this ride is packed on sunny days...in a pretty good way. Stop and have a hot/veggie dog from a stand, the Toronto streetfood.