I need to understand the industry benchmark for percentage of
information technology spend in relation to overall sales and SG&A. 
We represent a 150MM distributor of health care products to consumers,
physicians, EMS providers, and institutional health care providers.

Dlaff - -

Thank you for the interesting question.  

Almost all of the computer research firms - - including Gartner Group,
IDC, Meta Group and Hackett Benchmarking - - track IT spending by
industry.  The best overall breakdown freely available on the Internet
is Meta Group’s Metricnet site:
Metricnet Home Page
http://www.metricnet.com/

There are several breakdowns by industry listed here:
"IT Spending Metrics"
http://128.121.222.187/data_access/indexspend.html#G

The site requires registration to get to its annual survey of IT
professionals but the data is freely available.  More than 10,000
companies are represented in the survey and spending is shown as a
PERCENT OF TOTAL REVENUES.  The measure is used because of the ease of
comparison across industries.

Note that spending dropped for almost half of the companies after
September 11, 2001.  More recent surveys indicate that there is a
cautious recovery going on and some areas, such as security are being
pushed by the U.S. government:
C/NET
"Tech exec rallying cry is cautious" (Dec. 9, 2002)
http://news.com.com/2100-1001-976529.html?part-dht&tag=ntop

Overall corporations spend 3.61% of revenue on IT, but here are the
ranges for the industry categories surveyed:

Chemicals: 
2000: 3.09% 
2001: 3.51% 
2002: 2.68% 
 
Construction & engineering: 
2000: 1.55% 
2001: 2.03% 
2002: 1.43% 
 
Consumer products: 
2000: 3.52% 
2001: 4.33% 
2002: 3.64% 
 
Electronics: 
2000: 3.14% 
2001: 3.20% 
2002: 2.95% 
 
Energy: 
2000:  2.56% 
2001: 4.71% 
2002: 2.2% 
 
Financial: 
2000: 6.76% 
2001: 6.09% 
2002: 6.64% 
 
Food/beverage processing: 
2000: 2.31% 
2001: 2.56% 
2002: 2.13% 
 
Health care: 
2000: 4.33% 
2001: 4.81% 
2002: 4.42% 
 
Hospitality & travel: 
2000: 1.71% 
2001: 1.72% 
2002: 1.55% 
 
Information technology: 
2000: 4.13% 
2001: 4.68% 
2002: 5.13% 
 
Insurance: 
2000: 3.78% 
2001: 4.11% 
2002: 3.49% 
 
Media: 
2000: 3.66% 
2001: 3.95% 
2002: 4.13% 
 
Metals/natural resources: 
2000: 1.84% 
2001: 2.30% 
2002: 2.01% 
 
Professional services: 
2000: 5.11% 
2001: 6.39%  
2002: 5.12% 
 
Retail: 
2000: 1.64% 
2001: 1.80% 
2002: 1.63% 
 
Telecommunications: 
2000: 5.79% 
2001: 5.88% 
2002: 6.40% 
 
Transportation: 
2000: 3.79% 
2001: 3.93% 
2002: 4.17% 
 
Utilities: 
2000: 3.61% 
2001: 3.90% 
2002: 2.43% 
 
Google search strategy:
benchmarking + "IT spending" + industry

Best regards,

Omnivorous-GA

Exceptional answer with highly qualified free info sites to quantify.
Extremely quick turnaround time. - Thanks for the effort