You should file this incomme and related expenses on a Scheduele C. Companies only have to issue a 1099-MISC if the amount is over $600 or more. Some companies wont allow you to make more than $600, so it's best for you to keep track yourself. I have set up a spreadsheet.
I keep a little pocket calendar in my purse with the jobs for the day and write my beginning business miles and ending miles. Be sure to write off the required purchases for the shop, ie gas, food, business use of internet, long distance telephone, membership fees if you've paid any (Shadowshopper or other similiar sights, MSPA fees), office supplies-paper/ink for printing paperwork. If your tax return has always been simple and you've done them yourself, I'd suggest a tax preparer. You may be missing a lot of deductions if you aren't aware of all you can deduct. Mileage is also a big deduction, so be sure to keep track. The rate for 2006 is $.445/mile, for 2007 is $.485. I had over 4000 miles (most of my jobs are at least 30 miles one way since I live in a rural area) from July-Dec, which added to a significant amount on my tax return.