In general federal securities law comprises several statutes (mostly codified in Title 15), the rules issued by the Securities Exchange Commission, and reports of decided cases.
A security is any interest in a publicly traded company or according to the Securities Act of 1933: The term security means any note, stock, treasury stock, security future, bond, debenture, evidence of indebtedness, certificate of interest or participation in any profit-sharing agreement, collateral-trust certificate, preorganization certificate or subscription, transferable share, investment contract, voting-trust certificate, certificate of deposit for a security, fractional undivided interest in oil, gas, or other mineral rights, any put, call, straddle, option, or privilege on any security, certificate of deposit, or group or index of securities (including any interest therein or based on the value thereof), or any put, call, straddle, option, or privilege entered into on a national securities exchange relating to foreign currency, or, in general, any interest or instrument commonly known as a 'security', or any certificate of interest or participation in, temporary or interim certificate for, receipt for, guarantee of, or warrant or right to subscribe to or purchase, any of the foregoing." 15 U.S.C. §77(b)(a)(1).
The SEC website contains summaries and the text for some of these laws. An overview of specific statutes as well as a history of securities law can be found at the Legal Information Institute.
U.S. statutes can be found on a variety of free and fee-based sites:
U.S. Government regulations are first published in the Federal Register and then codified in the Code of Federal Regulations or CFR. Title 17 of the CFR deals with the SEC.
The SEC summarizes some of its most important regulations here:
There are several online sources for the Code of Federal Regulations:
State laws that regulate securities are called 'Blue Sky Laws'. Generally, these laws pre-date the SEC were enacted to protect investors from fraud.
CCH's Blue Sky Law Reporter brings together information on all fifty states including statutes, rules, policy statements, interpretive opinions, no-action letters and decisions. This reporter is available from CCH, Lexis and Westlaw.
There is also Secured Transactions smartbook from the Illinois Institute of Continuing Legal Education that covers Illinois.