Apple’s (AAPL) share of the U.S. PC market is still shy of 10%, according Gartner’s first quarter 2011 report, but some parts of the country are more Mac friendly than others.

Drawing on research gathered between June 2 and 8 by Chitika‘s ad network, which serves more than than 70 million impressions per day, MacDailyNews reports that San Francisco is the country’s No. 1 Mac-using city with a 24% market share. New York City is No. 2, with 23.3%.

Six of the top 10 Mac cities are in California, but statewide Apple’s share is only 14%. That puts it behind Vermont (19.55%), Hawaii (19.41%) and Maine (15.99%). To find the lowest concentration of Macs you have to travel to West Virginia or Wyoming (4.19% apiece).

Perhaps it’s time Jackson Hole got an Apple Store.

Click on Chitika’s map to check out the Mac usage in your state. (I found it worked better on Safari than on Firefox.)