The best thing you can get for your dog is quality dog food. What do you plan on feeding? I feed and recommend chicken soup for the pet lovers soul.
I also think that dogs NEED the two following things... a crate/kennel and natural bone chews.
My weim LOVES her kennel, it's her safe place, she loves to be in it. The only time it's shut is when we're gone or asleep. It is a safe place for her to be.
Chewing is good for teeth and helps fight off boredom. Note I said natural bones, rawhide is only so digestible. Natural bones are better and last longer. My dogs also love pig ears. My mom orders bones for me that are "sliced", they love those because they can eat the marrow out of them. Beware of very thin bones, or bones that feel really light, they can break and splinter.
Nail Trimmers. The pliers kind, and make sure you use them.