A: There seems to be a couple of options for you to check out.
USDA AMS would have price information on Edible and Inedible tallow.
The ams web site is:
http://www.ams.usda.gov/
There is a daily report. The daily report is NW_LS442 is
USDA TALLOW, PROTEIN, AND HIDE REPORT - FOB CENTRAL U.S.
and can be found at:
http://www.ams.usda.gov/mnreports/nw_ls442.txt
The site allows a search for past reports. The information is probably also in an annual report.
The Annual Meat Trade Review has a summary for the review for the price of Tallow. The Annual Meat Trade Review is also available on the web for several years before 2008. 2008 appears to be the most current.
http://www.ams.usda.gov/mnreports/lsancmtr.pdf