It is true that all self-employed businesses must pay taxes on a quarterly basis. Since you started your business in 2008 and really started generating profit in June, I suspect you would not have made a tremendous profit in your first year of business.
I would also tend to think that you would not be subject to a material tax liablity in your first year of business as there are a number of allowable deductions that you can claim in your website. Thus, the net profit that may be subject to tax would be considerably less than what you may think.
Furthermore, as far as the tax liability and estimated tax payments, your are correct to be concerned about not having paid these taxes. But, on the other hand, the IRS allows you to pay these taxes either in Jan 15th or on April 15th 2009 without incurring penalties or interest assuming you meet any of the following circumstances:
1. If your 2008 federal tax withholding and payments are at least as much as your total 2007 taxes (110 percent of your 2007 taxes if your income is more than $150,000).
2. If the balance due on your tax return is not more than 10 percent of your 2008 total taxes, assuming you've made your estimated payments on time.
3. If your total 2008 federal income taxes due when you file your 2008 tax return in April 2009, less any withholding, is less than $1,000.
Thus, it is a function of how much profit you have generated from your business along with how much your other income from your regular W-2 job, if any, has increased (and how much you have withheld for Federal taxes) that is also material to the overall situation.