check out bike pirates on bloor, just east of dufferin. volunteer/charity run shop.
take your bike in with any problems, tuning issues, upgrades, etc + they have all the tools/used parts you'll ever need to fix/upgrade your bicycle.
the amazing thing about the shop is that the volunteers will tell you exactly how to fix/upgrade your bike, while making you do it yourself. this is how i learned the basic/intermediate skills of bike maintenance. very laid back, easy going environment.
check out bike pirates here
glad you are so excited about biking!