I work at a company with a NAICS code of 423830 (same as SIC 5084)
which means we sell industrial machinery  and equipment. 
Specifically, as a distributor of maintenance, repair and operating
components we encounter the situation where our products may be used
either in a production or repair capacity for export to an affected
area.   In addition, domestic customers may ask for proof of such
compliance prior to purchase for items produced in the US and exported
to affected countries. As compliance directives become more stringent
intra-nationally, I'm expecting to receive an increase in requests for
compliance.  Export customers, namely in China and the European Union,
may require proof of compliance to avoid their shipments being stopped
in transit.

I'd like to know how other companies in my line of business are
responding to these these types of requests when a customer is
ordering material. Are companies in my same line of business providing
this information now and do they plan to in the future?  Or, are they
responding with something along the lines of "we don't know if this
material is compliant" in order to avoid the extra work?

Take a look at www.bayworth.com They have specialist in the WEEE and
ROHS area and can probably help you.

Just to add to your query. If you are supplying replacement equipment
or equipment for repair of items put on the market before July 2006
then they are permitted to fall outside of WEEE and ROHS directives. I
would need more information on your products to comment further.
However, In general I can say that most companies are now taking the
issue seriously and are putting in place systems and procedures that
ensure compliance. You can not take the approach of "we dont know"
because if your customer is audited the legislation allows for their
suppliers i.e. you! to be fined as well. The potential fine could also
be unlimited if you are found to be in breach of the legislation
particularly if you knowlingly breach it. The previous website can
probably help you with current best practice.
Also note that the legislation not only covers lead but Mercury,
hexavalent Chromium, halogenated flame retardants etc. You need a
thorough product and material review to ensure compliance as you will
find that non compliant matrials turn up in the strangest places.

Thanks for the help. I wonder what would happen if we made our default
answer: "these items are not compliant". Maybe that would eliminate
all of this work entirely at the expense of losing an occasional order
here and there. What do you think?