costco is the best place/price for winter tires, especially during promo.

so when you look up tire sizes and it pops out "195/65R15" ...the R15 is your rim size, and 15 means it's a 15" rim. R16 would be a 16" rim, etc. the other two numbers are your tire tread sizes (the rubber stuff).

if i were you i would buy the tires from costco because they're new, you get cheap install and the tires are very very well priced, and a steal on promo. if you buy 15" rims from kijiji make sure they fit your car. not all 15" rims are the same because they have different bolt patterns, so the rim needs to match your car bolt pattern. google this if you need to know.

hope this helps a real newb.