Has anyone seen this before? I got it from India as a gift but I have no idea what it is called or how to take care of it. Thanks
Looks very similar to Naringi crenulata which is found in India. More information can be found on this Encyclopedia of Life page.
I believe that the scientific name of that leaf is Aegle marmelos. I think that a good place to start is by reverse searching the Google image and then seeing if there is a scientific name associated with it. If there is not a scientific name associated with it, you can search for the scientific name based on the organism's common name.
Following on from Kurt's response, there is a similar irregular margin version called Hesperethusa crenulata which is perhaps apparently used as a beauty cream, Thanaka, unverifiably promoted as "skin whitening" i.e. bleaching by some sellers, antioxidant, antibacterial and moisturizing, mostly famous in Burma, and which can be bought around the world. So it's also a cultivated tree and you'll find a lot of common and cultivar names for it. the sources of information for it are confused, there seems to be Limonia Acidissima and Limonia crenulata which are closely related. Perhaps both are used medicinally.
Thanaka also appears as Thanaka tree with reference to Hesperethusa so it seems that it has some Natural remedy / Ayurveda properties from the same plant in Burma and India.
In depth page for it here: http://idtools.org/id/citrus/citrusid/factsheet.php?name=Hesperethusa+crenulata