As a physician, I would like to perform disabity exams for the social
security administration. What do these exams entail and who do I
contact to get started?

Hello.

From the Social Security Online web site:

"Health and school professionals are involved in the disability
determination process in a variety of ways:
* As treating sources or other medical sources who provide medical
evidence on behalf of their patients;
* As consultative examination (CE) sources to perform, for a fee,
examinations and/or tests that are needed; and
* As full-time or part-time medical or psychological consultants
reviewing claims in a disability determination services (DDS), in one
of our regional offices, or in our central office."
Source:
Social Security Online Disability: "Role of Health and School
Professionals"
http://www.ssa.gov/disability/professionals/role.htm

From your question, it sounds like you're interested in becoming part
of the "consultative examiner" program.

See the description on the Social Security Online web site:

"Consultative Examiners for Disability Determination Services (DDS)
In the absence of sufficient medical evidence from a claimant’s own
medical sources, Social Security, through the State DDS, may request
an additional examination(s). These consultative examinations (CEs)
are performed by physicians, osteopaths, psychologists, or in certain
circumstances, other health professionals. All CE sources must be
currently licensed in the State and have the training and experience
to perform the type of examination or test that Social Security
requests.
Fees for CEs are set by each State and may vary from State to State.
Each State agency is responsible for comprehensive oversight
management of its CE program. The Professional/Medical Relations
Officers for your State can provide additional information about
performing consultative examinations for the DDS in your State."
Source:
Social Security Online Disability: "Role of Health and School
Professionals"
http://www.ssa.gov/disability/professionals/role.htm

To become a consultative examiner, you'll need to contact your local
Disability Determination Services branch. There's a comprehensive list
of these branches, classified by state, on the Social Security
Administration's web site.
See:
"Professional/Medical Relations Officers in Your Area," hosted by
Social Security Online Disability:
http://www.ssa.gov/disability/professionals/procontacts.htm

The complete details for what disability examinations involve are
available in a 170 page document called "The Blue Book."
See:
Social Security Online Disability:
"Disability Evaluation Under Social Security"
http://www.ssa.gov/disability/professionals/bluebook/Contents.htm

Social Security Online Disability:
"Disability Evaluation Under Social Security: Blue Book"
http://www.ssa.gov/disability/professionals/bluebook/2001bluebook.pdf
(PDF format, so the Adobe Acrobat Reader is required. If you don't
have that, visit Adobe's web site:
http://www.adobe.com/products/acrobat/readstep2.html ) 

search strategy: disability, "social security", physician,
"consultative examiner", "consultative examiners", "consultative
examination"

I hope this helps.

excellent job, not expected
I spent time on Google without success.