d517, it appears you don't currently live in Phoenix. If so, are you considering an investment in Phoenix Real Estate? The definition of "a good time to buy" needs to take into consideration many factors. I would say now is better than it was 6 months or even a year ago, if you have 20% down, or are planning to use FHA financing. If you don't have 20% down or don't like the higher cost of FHA buying, today's lending environment really is pretty crappy, regardless of the purchase price on homes. If you are looking to make an investment, it is still difficult to find a cashflowing property in Phoenix. They can be found, but it's difficult. If you are planning to owner occupy, and are worried about prices going lower, you should be. Pricing are going lower right now. I've have a guess when the lowet price will be, but it's a SWAG at best, and about as meaningful. Today, I can say I would be a buyer, if I could buy something at least 5% lower than "market value", as demonstrated by previous sales of an owner occupied home. I would also only be a buyer, if I was buying the nicest home, on the nicest lot, in the nieghborhood. I'd be that picky, or I'd wait.
At any rate, help us out, and provide a bit more motive about what you plan to use the home for, where you are looking, etc. There are actually parts of the valley/market that are actually seeing a price increase right now, so it's not a very simple yes/no answer.