Welcome!
- Get quotes for insurance before buying anything
- A letter of experience from your old insurer (as well as proof of previous motorcycle licence history) may be beneficial if you can find an insurer willing to accept it and give credit for it.
Others also touched on both of the above, but they're important. Focus on these, especially the first one...before you put any money down on anything.
As for when to buy....NOW is good, so get going. The market is at the absolute bottom around this time of year - people that have bikes they no longer want will be highly negotiable on pricing, particularly if they want to sell to free up funds to purchase something new themselves. Around March people start to get a whiff of spring in the air (well, maybe not this year if the forecast goes as predicted, but that's another story) and the motorcycle market wakes up, so expect prices to creep upward - by April prices will be at their peak as everyone is looking for bikes and it's very much a sellers market, not a buyers market.
Our licensing system for MC's is fairly simple - when you buy (presuming you're looking at used?) you need the owners copy of the ownership document (a small green slip of paper that will show his details as well as the bikes details), a bill of sale, and a UVIP - the "Used vehicle information package". Make sure to get the UVIP, and look at it - it will show in clear language the ownership history of the bike and confirm that it's actually in his/her name, as well as (most importantly) if there's any liens (bank loans mainly) against the title. You don't want to buy a bike with a lien on it obviously, but some people try, hence the UVIP being important. It's supposed to be the sellers responsibility to provide/show you the UVIP at the time of sale...if they don't, you have less of safety net against anything unexpected, and when you go to switch the ownership and register the bike they will force YOU to buy it instead...at which point skeletons may come out of the closet. So make sure potential sellers have it and are willing to show it to you...and that it's recent, not a 6 months or a year old.
With all that in hand, you need to get the bike to a shop that does motorcycle certifications (not all do, so you may wish to go to a motorcycle centric shop) and get it certified. The cost is usually between $60-$100 plus any work it may need to make it certifiable.
How to get it to the shop is your choice/problem - if the previous owner will ride it there for you (if it's still plated and insured), that's easiest...otherwise you may have to trailer it there. U-Haul rents motorcycle trailers for cheap, that's always an option.
Once you have the certification paperwork, arrange insurance - your company/agent/broker will send you a temporary coverage slip via email on request and you wait for the full paperwork in the mail later.
Once you have everything (Insurance, ownership, UVIP, and certification papers) you go to a Service Ontario centre and you can change the registration into your name and get your plates & sticker in one fell swoop. Plan for some time there, these centres (especially the ones in Toronto or the GTA in general) can be crazy stupid busy.
Once you have your plates, you're good to go...whenever the weather turns.
As for where to ride, well, getting out of Toronto is the first challenge... After that, head Northeast (Think 100-200K circle of Algonquin Provincial Park) and you'll find some interesting roads. Ontario alone is over 10 times the size of Ireland as a whole, so you'll find lots to explore.