Below are some computer-based instruments that can be used to assist in the evaluation or diagnosis process for some disorders.  This should not be the only tool used in the diagnostic process, but it can assist with the process.  Some of the instruments below offer a free trial and some just provide demos/product reviews online.

Systematic Analysis of Language Transcripts (SALT)
http://www.languageanalysislab.com/
Try SALT demo here http://www.saltsoftware.com/salt/downloads/

Computerized Profiling for Phonology (PROPHET)
http://www.computerizedprofiling.org/cpinfo.html
Try PROPHET here http://www.computerizedprofiling.org/downloads.html

Nasometer
~http://www.kayelemetrics.com/index.php?option=com_product&controller=product&Itemid=3&cid[]=78&task=pro_details
~http://www.cstr.ed.ac.uk/research/projects/artic/nasometer.html

Computerized Articulation and Phonology Evaluation System (CAPES)
http://www.pearsonassessments.com/HAIWEB/Cultures/en-us/Productdetail.htm?Pid=0158123999&Mode=summary
The Child Language Data Exchange System (CHILDES)
http://childes.psy.cmu.edu/

Let me know any other computerized diagnostic tools.