Getting an Indian visa can make standing in line at the DMV look like a foot rub! Thus, many people pay a service to help them and for many people it is well worth the money. If you don’t mind the hassle, you can always do it yourself for about half the price, but be prepared, you will want to scream! Generally these services will help you gather your paperwork, fill out the application and then bring your passport to the consulate to be stamped for you. Here are a few authorized agencies.
Contact the government where you are a citizen as every country is a bit different. For US Citizens, you can get information about passports here: http://travel.state.gov/content/passports/english/passports/apply.html
Visit the website http://travel.state.gov/content/passports/english.html/ of The USA Passport Office.