Ok! I have read on here until my eyes feel crossed and my neck hurts!

I want some Quality Australorps to start a small flock.
Please help me figure out what my options are and where I can get them. I prefer day old chicks. At least that is what I am thinking. I have not seen any Australorps at Rural King or TSC this year so far. Should I just order from a hatchery? I am concerned a little about the Quality of birds I might get.
Should I buy from a private breeder? Who has a good reputation and will have chicks available in the next few weeks?
Please don't hesitate to give me some direction or options. I realize the best is always an opinion formed by each individual, but I need some options. Also feel free to send me a private message.
I am new to chickens but not breeding. I have bred dogs for many years and bred many winners, Grand Final winners, & show Champions. I just want to get a start in Chickens and Australorps I think are gonna be my breed of choice?
Should I keep only one breed or mix in other breeds? Help!!
I am in Southern IL.
Dan