50 state statutory surveys and charts are a very useful resource of locating and comparing the laws on a subject across all states.
The National Conference of State Legislatures (NCSL) tracks a number of areas of law across all 50 states. Privacy and data security is one of its areas of interest. All guides are freely available online.
The Uniform Law Commission (also known as the National Conference of Commissioners on Uniform State Laws) proposes uniform state laws across a broad range of subjects. Many of these uniform laws have been adopted, in whole or in part, by state legislatures.