Salary.com is fine for a ballpark rough estimate nationwide.
But their locally adjusted numbers simply use the national average and adjust it based on the average difference in salaries for all occupations for the specific area you are looking at. They do NOT take supply and demand for a particular occupation in a specific area into account.
I can tell you that most software developers at my company are making between 45 and 70 k depending on experience. This includes positions in various locations around the country. I've had some prospects for a couple of programming jobs here in Oregon but they only paid 40k and that's substantially less than I'm currently making.
From Salary.com:
"The data in Salary.com's premium products (e.g., the Personal Salary Report, Compensation Market Studies, and the Job Valuation Report) is fully scoped. This means the underlying survey data for a given benchmark job has been segmented to reflect pay practices specific to various locations, company sizes, and industries. These are factors known to strongly affect pay and are essential when making professional salary decisions for a given job.
Furthermore, the Personal Salary Report and Job Valuation Report may be used to account for differences in estimated market value arising from personal attributes such as years of experience, performance, education, and other compensable factors known to have some influence on an individual's pay.
In contrast, the Salary Wizard's free answers are based on salary values averaged across survey responses from all company sizes, all industry types, and all locations, and offer no personal customization. The Salary Wizard applies a geographic adjustment factor based on the city or ZIP code specified in order to give users an initial sense of local market conditions and to give some confirmation that the correct job title and description have been selected.
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