Go to E Bay and look up the battery by brand and model number of the laptop. Go by or call a local computer store and ask. Go to Toshiba website and under accessories look up the battery for your model.
Depends on what the exact model number of your Toshiba laptop is. Without the model number we cannot help you. The model should be on the underside of the laptop, or possibly in the battery compartment. Take the laptop into a computer store and get them to identify what battery you need.
cheapest solution to battery buying is ebay.com. Just put in your model number and the word battery, and it should show you a list of items for sale for your laptop. I recommend changing sorting order to lowest price.