Need expert in social network analysis/graph theory

I have a blog with reactions on main articles. My data is in a mysql database (normalized). I would like a social network drawn, based on a 'who reacts on who' relationship. The relation should have two attributes (weight - to be defined later) and time of reaction). There can be more than two reactions between persons (nodes) in the graph. Next to this, it should be possible to draw the same graph, but in a simplified form: only with the relations containing the latest timestamp. Finally some basic calculations should be made on the simplified graph (nodal degree, diamter graph, geodesic distance between two nodes, clustering coefficient,...). Don't need a fancy GUI. Text interface will do fine, but visualization of graph should be clear. Provide clear and documented code, so I can find my way around if I like to addapt something. Please provide samples of previous work.