I liked the Goooddeedseats.com site, although I wish I could have found cheaper Suns tickets. But I've seen more expensive ticket sites too. They did have a decent selection of seats available when I was shopping.
I love this site. It offers a lot of good, vetted information on a lot of different topics. When I have a geeky-type question, I will often go to this site for answers, and I will usually be successful. Check this site out if you haven't already.