Giving the digits

Hello all,
Love reading the boards and I'm in need of advice. So about a month ago I deactivated my Facebook account and the few other social networking sites I had. I'm thinking of purchasing another phone that will not have a texting feature, just calls only. As you can tell, I'm ready to do away with boys and finally date mature men. However, I have some questions regarding when to give out your number. It seems as if most guys that you meet in passing (on your way somewhere) are usually interested in sex. The same thing goes for guys at clubs and bars. I usually like to meet men in more organic settings, get to know them, then give my number. What stipulations do you ladies have in giving out your number? Does a guy have to work to get the digits? Should there be standards set in place for giving out your number?