They seem to be around my area so why go too far, esp with potting mix or soil that stinks in the car.It also depends on the price, a few items can be big money.
Sometimes I may also go to the markets to get plants.
When I lived in London, my local market had a cracking garden stall and I used to buy all my plants and materials from there. Nowadays we head off to a large chain garden centre as I don't really know of any smaller suppliers round here.
I tend to buy my pots and such from Bunnings or Kmart where it's cheaper, but I prefer to buy plants from local nurseries where they know the plants and how to care for them and can give me great advice!
It tends to be Bunnings because there is a Bunnings next to a bus stop nearby which makes it easy for me to get to. Sometimes I order seeds online, and I got some fruit trees shipped to me from a nursery.