This document discusses some of the local and federal regulations governing the handling of radioactive materials:
http://www.perkinelmer.com/CMSResources/Images/44-73406gde_safehandlingradioactivematerials.pdf
See p. 7 and following for a discussion.
The Code of Federal Regulations, Chapter 10, contains the regulatory language. The CFR can be accessed here:
http://www.gpo.gov/fdsys/browse/collectionCfr.action?collectionCode=CFR
Select the year, and a new menu will appear listing all chapters in the CFR (there are 50 total). You can download all of Chapter 10 or just the pertinent bits.
As far as acquiring the actual material, I suppose you could go to Home Depot and buy a crapload of smoke detectors.