I don't have recommendations for software or consultants, but I do have a couple of references that you should look at:
Travis D
Leleu, Isabel G Jacobson, Cynthia A Leardmann, Besa Smith, Peter W Foltz, Paul J Amoroso, Marcia A Derr, Margaret Ak Ryan, Tyler C Smith, et al.
Application of Latent Semantic Analysis for Open-Ended Responses in a Large, Epidemiologic Study BMC Medical Research Methodology. 2011;11(1):136.
O'Cathain A, Thomas KJ.
"Any other comments?" Open questions on questionnaires - a bane or a bonus to research? BMC Med Res Methodol 2004: 4(1); 25.
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Stephen Simon
Independent Statistical Consultant
P. Mean Consulting
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