As of today, I added an email account for business. So as of this moment, I have both a personal email account and a business email account in my iPad. How do I keep contact information for the two accounts separate? Thanks.

What kind of account is your new business account? If it is Google, or Exchange based you can create and maintain a separate address book.

For a Google account, you have to set it up as an Exchange account. Here are the instructions.

Setting up Google Sync with your iOS device : Mail, Calendar, & Contacts - Google Mobile Help

Once you do that, and turn on the contacts syncing, to into Contacts. When you do you should have a red ribbon on the left page that says Groups. Tap that and you will see the new exchange/google account. Select that to see and add contacts to that account.

This should work about the same for any account you can set up as an Exchange account.

You may also see a Global Address List. You can select this to make searches, but you will not be able to add contacts or see contacts (until you do a search).