I received a call yesterday asking a question about a certain grass-specific herbicide and whether or not it was labeled for blueberries. I knew right off there there is only one grass-specific herbicide that is labeled for bearing blueberries, but was not sure on the specifics of the one in question. So, where did I go to find out? I go to CDMS.net for the label (http://www.cdms.net/LabelsMsds/LMDefault.aspx). Of course, and this cannot be stated strongly enough, the labels on this website are not considered the true label. The true, accurate, legal label is what is on the jug that one buys in the store. On the website, they are just examples of what exists and can give you an idea of what crops it may be labeled for and what pests it controls.
Now, some pesticides are not labeled in all states, so one must check that too. A site for that is kellysolutions.com, for example in Mississippi (http://www.kellysolutions.com/ms/). Not all states are represented by this website, but 36 of them are, so there is a good chance you can find what you need here too. Below is the image from the kellysolutions.com website on what states they cover.
So, next time you want to look up a pesticide label, take a few minutes to check these websites. Once you have found what you need, then confirm it with the label on the jug itself (and never throw out the label!). If you have further questions I would be happy to answer them too, just as I did yesterday. The labels can sometimes be confusing, so that is where Extension professionals come in to help interpret the meaning.