Sorry to hear about your cracked tooth. What can be done about a cracked tooth depends on how it is cracked and how it is bothering you. For example if it is only bothering you because you know about it then nothing may need to be done, but things can be done to notice it less.
If it is a front tooth and it is chipped a little then there is not a lot you can do at home. This would require going to a dentist and having him/her/other aesthetically fix the chip. This could involve a bonding, veneer, or crown.
If the crack goes into the center of the tooth (pulp chamber) then it is likely to be bothering you especially when you bite down and release. If this is the case then a root canal would be needed followed by any other treatment needed to fix the crack (crown, filling, core build up, etc).
If it is cracked between the roots; unfortunately, most of the time this requires removal (extraction) and replacement of the tooth. Hope this helps.
My best to you!
William F. Scott IV, DMD
By fixed, I mean -- get it crowned to help hold the tooth together. and prevent decay getting to the nerve of your tooth.
Bruce L. Elkind, DDS, PA