In the beginning it is very important to recognize the fact that in PR the focus must be directed to not a short-term, but a long-term relation with media. The first step here is meeting with writers in person. As a Harvard Business Review study claims, 95% of respondents had an in-person meetings before they built business relations. One of the easiest ways is to visit events hosted by media companies. The last ones represent huge spectre of events that differ from free of charge to $3000 per conference. List of events you are able to find in StartupDigest.com, where the best are introduced.
The next opportunity to meet a reporter is through introductions. Here LinkedIn can be helpful as it refers to mutual connections between you and a journalist and it is possible to ask person for introduction.
Connection with journalists online is very easy and convenient, as the majority of them use twitter or/and personal blogs. Your comments can help to introduce yourself before you actually will send an email.
It does not matter which form of communication you choose, but it is always important to remember that time is the biggest treasure for journalists and follow next advices:
1. do not ask open ended questions that require a long answer;
2. do not feel "friends", ask for coffee etc., in the case if you do not know him/her personally;
3. let understand that you do not want to become a hardship or burden.