Hi Joost,
I just saw Dan Edelstein present on “The Republic of Letters” at the MLA Convention. It’s a great project and one well worth building on.
Here are a few programs that might be of interest:
NodeXL ( http://nodexl.codeplex.com/ )
Gephi ( http://gephi.org/ )
ORA ( http://www.casos.cs.cmu.edu/projects/ora/ )
You might also look at the following posts from recent GC grad Jeff Drouin, who has been experimenting with social-network analysis for his Ecclesiastical Proust Archive. Here are a few places to start:
“Social Network Analysis of Magazine Culture” – http://magmods.wordpress.com/2010/10/21/social-network-analysis-of-magazine-culture/
Ecclesiastical Proust Archive – http://www.proustarchive.org/
You can also contact Jeff by email — I’m sure he’d be glad to help.
Best,
Matt