Do I need to report my earnings from Pepperlane to the IRS?
Yes, if it exceeds the minimum annual amount established by the IRS. Assuming that you haven't incorporated a business, any income you earn from providing services to clients you connect with through Pepperlane is considered self-employment income, so it is subject to Federal, State and self-employment (Social Security and Medicare) taxes, as well as any local income taxes that apply in your area.
You'll need to keep track of your income and your deductible expenses (keep those receipts!) in order to figure out your annual tax liability and make appropriate quarterly estimated payments.
For more information about how to calculate and report your self-employment income, make estimated tax payments and deduct appropriate expenses, check out the IRS's guidelines for self-employment income.
Unfortunately, Pepperlane is not able to provide personalized tax advice, so you may also wish to consult a tax professional for additional help.