First contact was via a recruiter on the phone who had some really basic questions (tell me about yourself, questions about relocation, salary, etc).
Next was a phone interview with three managers, which last about half an hour. About half of it was about my background and professional interests, and about half was behavioral questions (what would I do if I thought my manager were wrong about something, tell us about a time you had conflict at work, etc)
A week or so later I was flown in for a day of in-person interviews. The first was with three managers and again consisted of questions about my background, interests, with some behavioral stuff mixed in. The second was with members of team who would have been my peers and was basically a meet-and-greet. The third was with the branch head and was mostly about my interests, how I would fit, and a couple of hypothetical scenarios.
Overall, a very positive experience. Everyone was very friendly, very smart, and seemed committed to their jobs without being overly enthusiastic. Frankly, I can in fairly interested and left wanting the job and even more to work at the Home Depot's Headquarters. Unfortunately I didn't get the position, but still a great experience.