Thanks that is the information I need.
Due to the physical damage, it is likely the hardware use to recognize touch is also effected. Did you purchase any sort of AppleCare+ extended warranty when you bought the iPad?
Since you have a cracked screen this will not officially be covered under the normal limited warranty provided by Apple (and your original 1 year warranty would have expired). HOWEVER, ti wouldl be covered for around $49 under AppleCare+ replacement service but otherwise you would need to pay normal repair costs, sadly.
offers a one-time courtesy (free) screen repair/replacement for iPads that are still under warranty, as well, but in your case you would need that extended AppleCare+ warranty. You would need to take the iPad to a local Apple Store and talk to a "Genius" there as it is under their discretion that replacements may be made. Generally, it's due to an "unfortunate circumstance" (My kid ran into me from around a corner and bumped it right out of my hand) and not given for carelessness (I left it on the top of my car and drove off.) However, do NOT mention that you are aware of this service.
If you don't have the AppleCare+ this does not work for you, so you might choose to use a reputable 3rd party repair service. You can usually expect to pay around $149 currently, if it's just the glass and digitizer (touch hardware).
Since you are in the US, I would recommend using iResQ in this case as they offer free diagnosis and recommend the most economical repair for you.:http://www.iresq.com/ipad-repair/ipad-2-repair-replacement-service-parts.html
They also have a very fast turn-around.