With gas prices skyrocketing into the $4.00 plus per gallon price, driving can really up your cost of operation.  According to IRS.gov, you cannot directly deduct mileage that is calculated to and from your regular places of business (home to work, work to home).  Now this only means that you cannot deduct mileage to and from your house and homebase of work.  You can however deduct mileage cost to and from work sites that you do not normally work at.  Imagine if you arrive at your office and need to go on location for a recording or live sound gig, you can write off the mileage that is calculated from your office to your gig.  Below is the IRS announcement of its standard mileage cost for business driving and the guidelines to which you can writeoff business mileage.

IRS Standard Mileage Rates

IRS Guidelines for Business Mileage