For the relevant regulations, you could begin at the HHS website. Or, you could begin with the official source of Federal regulations, the Code of Federal Regulations.
Task 1: Find the Privacy Rule
Beginning by navigating to the CFR (you can type in "code of federal regulations" in the Westlaw search bar, and select when it appears), search for "privacy rule". You'll see that some of the results relate to HIPAA, while others relate to other agencies, e.g., the Commodity Futures Trading Commission.
Be sure to check the headings for the section you select. If you used the HHS website or have other resources at hand, you should be able to navigate to the correct sections of the CFR.
Federal Register on FDsys - 2013 Final Rule to modify HIPAA Privacy, Security, Enforcement, and Breach Notification Rules (under HITECH and GINA).
Task 2: Find the Docket for this rule on Regulations.gov.
Method 1: When you have the docket number, use it. See top/bottom of the Rule in the FR
Method 2: Search by keyword, limit by agency and status, sort by date.
result: you should find this docket for the most recent final rule (78 FR 5692, 1/25/13).
Task 2a: Find Public Submissions for related regulations
Search for HITECH or HIPAA, limit to HHS, limit to public submissions.
HHS.gov example: HIPAA for professionals.