Below please find a link to Market insider on this site you can enter a zip code and find out information about crime, schools, home values, sales trends, you can also compare areas. I hope this helps you.
Keller Williams Realty
Trulia has a Crime heat map that you can use to get a general idea. Find the HEB area here: http://www.trulia.com/crime/#!dallas-tx/14/32.82471,-97.1498
You can also go to the city police department and ask for crimes in a specific neighborhood or for an address that you are interested in.
Here is a blog on my website about this: http://finddallashomesforsale.com/safest-neighborhoods-in-dallas/
If I can do anything to help you, please don't hesitate to give me a call.
B&B Realty Group - Keller Williams Elite Park Cities