The iPad does not support printing via Bluetooth. Even if you somehow get the printer to pair, it still is not going to work.
Here are the only methods (so far and that I know of) to print from the iPad.
Some printers are directly compatible with AirPrint on the iPad. This includes several HP printers and a smaller selection of Canon and Epson printers. Be absolutely certain the printer supports AirPrint before buying. Some printers may require a firmware update to work. These are usually available on the manufacturers site. If you get this kind of printer you can print directly from within apps that support the feature, which is many.
iOS: AirPrint 101
Of course some of us already have printers and do not want to buy a new one. There are a couple ways to do this.
One is to use a printing app on the iPad. The current favorite is Print and Share. It will work with most wi-fi printers, and those that it won't work with can be made to work with an additional program on the computer. Print n Share is currently the only app that will work with the built in AirPrint feature in many apps. It must be launched before you try to print in the other app. Most (or all) other print apps can only print pictures and/or files that have been copied to that app via Open In or other method.
The second method is to load a program on the computer that will emulate an AirPrint compatible printer. Your computer must be on and have the printer available to it. The cheapest (free) is Airprint Activator. More features can be had with FingerPrint (mac and windows) and Printopia (mac only).
There is a third way. A few printers (mostly HP's again) can be set up with their own email address. PDF attachments can be sent via this address to be printed. The last review I saw (several months ago) said it could be quite slow (big files not recommended), and sometimes the emails got lost and never printed. The advantage was that you could literally send/print from anywhere you have an internet connection.