IRS tax audit, help!

收到IRS的信，要查我2004的帐。那一年，我有w2收入，还注册了公司（LLC)，申报了$10k business loss ( mostly travel expense, trip to China, utility etc.) in Schedule C。

Anyone experiences tax examination thru mail before??

请问我要请CPA吗？What is the catch if I handle it myself? Do I have to mail all the receipts ( will be lot ) to IRS? Or just my quickbook record will be good enough?

Thanks in advance for your suggestion!!

晕