Any home improvement store like Home Depot or lowes I'm sure would carry cantilever umbrellas. If not, always try Wal-Mart, they seem to carry everything nowadays.
The best, and cheapest, place to buy a large patio umbrella is through amazon.ca or ebay.ca. These websites allow you to compare rates and get a good deal.
The best place to buy umbrella replacements would be at www.mjjsales.com. This place is trustworthy as it has already been around for 10 years. It also sells umbrella replacements at a reasonable price. As I am not sure where you are situated, that's the best site I can provide you with. If you know any local places that sell patio umbrella replacements, ask around.
the best place to go to get a really good sun umbrella is your local garden shop or if you live by the beach got to the beach shop and they should have some good selections for you to choose.
If you want umbrella with lights it would be best that you look at your local hardware store. If cannot find one, you can always just put lights under the umbrella.
You could make your own out of some type on canvas or maybe buy one on ebay.com. It would probably be the best to just buy a new umbrella at a garage sale though.
best buy is the best place
You can buy it at best buy
I personally think that there isn't a best brand when looking at patio umbrella's. All brand provide proper shade and will last you for a few years as long as you take care of it.
buy one
the best place to buy a car i guess is at a place were people normally get cars.
I think i would check out Amazon.com to see if they had a unique patio umbrella that fir what you were looking for. Overstock.com is also a great place to find rare and unique items.
Minecraft.net is the best place.