Business Taxes
Taxes will vary depending on your business. Businesses with no employees won't have payroll taxes. Businesses not in retail sales won't have sales taxes. Figure out which taxes the federal government, your state government and sometimes the city requires you to collect.
I have found that the best way to handle taxes is to consider them a cost of doing business. No different than the cost of your supplies, insurance, equipment or any other expense you have in business. As you earn revenue, set aside a certain amount for taxes (say 25% of revenue) then send it in to the appropriate agency at the appropriate time. Simple and easy.
For new small businesses I recommend using a payroll company to make sure quarterly business taxes are paid and processed properly for at least the first year or so.