I'll be needing winter tires soon 18s stock rims. What's the best place to get some tires from.

 

Tire rack, discount tire, ebay, take your pick. Call around to local tire shops and get the OTD price for a few different types and see who is the lowest. Keep an eye out for mfg rebates.

I've always had great luck with craigslist / fbook market place. A few weeks ago I picked up a set of 1 season old blizzaks for my dad for $60!! It was some old lady who sold her car and to her the tires we useless. If you know ahead of time that you need winter tires, then always keep an eye out on either site.