Any recommendations for a good collar/leash training?

Your approach is good. Obviously you are getting an unknown dog, so you will need to assess your dog. Harnesses for dogs are far better than dog collars for training your dog to walk by your side, without pulling, as collars can cause damage to the dog's neck/trachea. Vets recommend harnesses. I have left some links below for dog harness reviews and an easy to follow 10 step training routine to train your dog to walk nicely, which is designed to be used along with a dog harness and leash. You should, with a little patience be able to train your dog yourself and it is a great way to get to know each other. Great news you are adopting.