If you can find a place which offers both obedience AND agility, that would be good.

But if not, then for the obedience, please don't go to a PetCo. You want an instructor who HAS dogs! Some places the instructor has book training only, passed a course and is qualified to teach. You will find instructors with dogs in Agility, Flyball, even field trials, and all are great. They have worked with dogs and know what to look for, how to interpret the dog's posture and help you to understand it.

Agility: see which program offers the most competitions in your area. There are AKC Agility trials, and also APDT* Agility trials. You will find one is more popular in your area, with less travel required to get to a trial.

* American Pet Dog Trainers

Some folks avoid AKC even though they have an AKC dog, because AKC only permits pure breds to compete. Folks feel if you have a mix and are willing to work with it, you are a good owner and should be encouraged. I think AKC just set up a mix breed program, in the past month. Anyhow, that is a bit of background. APDT takes all dogs, purebred and mix.