Path (graph) shower utility

[Durumdara]

Hi !

I need to create a program that read eml file headers, analyze the
receive tags and create a path database. I finished with this program
section.

But I want to show a graphical summary about the paths.

This is (what I want to show) like a graph - show ways, stations, etc,
and I want to show the strength of lines (how many of mails use this way).

Can anyone known about a freeware tool, software, or python module that
can show graphs with best alignments ?

Please help me. Thanx for it:
dd


Ps:
The OS is Windows XP:
I tryed with pydot, but this code created many 0 length files.

import pydot

print pydot.find_graphviz()

edges=[(1,2), (1,3), (1,4), (3,4)]
g=pydot.graph_from_edges(edges)
g.write_svg('graph_from_edges_dot.svg', prog='dot')
g.write_svg('graph_from_edges_neato.svg', prog='neato')
g.write_jpeg('graph_from_edges_dot.jpg', prog='dot')
g.write_jpeg('graph_from_edges_neato.jpg', prog='neato')

 >>>

{'fdp': 'c:\\Program Files\\ATT\\Graphviz\\bin\\fdp.exe', 'twopi': 
'c:\\Program Files\\ATT\\Graphviz\\bin\\twopi.exe', 'neato': 
'c:\\Program Files\\ATT\\Graphviz\\bin\\neato.exe', 'dot': 'c:\\Program 
Files\\ATT\\Graphviz\\bin\\dot.exe', 'circo': 'c:\\Program 
Files\\ATT\\Graphviz\\bin\\circo.exe'}


Thanx for help: dd