All starting rates are 50% of the mechanic's base rate. This information is readily available.
http://www.wdol.gov/dba.aspx

In Local 8 Santa Clara County it's $63.44 for a mechanic's base rate. 50% of that is $31.72.

In Local 80 Raleigh the base Mechanic's rate is $38.14. 50% is $19.07.

I posted these two because they are the Highest and the Lowest in the country. These numbers do not factor in that companies can pay mechanics more if they want.

Also, keep in mind that the cost of living in these two areas are vastly different. You would have to make roughly $41.50 to start in San Jose to have the same buying power as you would if you started in Raleigh. Or you would have to start at $14.58 in Raleigh.

Furthermore, the fringe benefits are equal.

http://www.bestplaces.net/cost-of-living/raleigh-nc/san-jose-ca/39666