I have found several for you. In addition, I can take a look at your trees as well and take samples if necessary for further diagnosis. If you would like me to do that, please call our office at 217-752-2191.
As far as on-line resources this is what I found: (1) Penn State has a good site devoted to conifer diseases. It has good advice and descriptions, but no pictures. http://www.ppath.cas.psu.edu/EXTENSION/PLANT_DISEASE/pine.html (2) Purdue University is reporting a lot of "conifer dieback" this year. they have produced the following publication for download. http://www.ppdl.purdue.edu/PPDL/pubs/briefs/Conifer-Dieback.pdf (3) Univ. of Minn. has a good site that deals with conifer diseases plus has a link to their site on conifer insect pests. Good pictures but no control measures. http://www.entomology.umn.edu/cues/dx/con_dis.htm
I would use the U. of Mn. site for diagostics and the Penn State for how to control, unless you have "conifer dieback".
Hope this helps and if you would like me to take a look at the trees, please call.