Reconnecting America, a transportation advocacy organization, just published Transit Space Race 2013. To see the Sacramento area projects, click on the < 3 million tab, and then sort by state. The eleven projects will be at the top of the list. The transit agency link in the right-most column links back to a page or website about the project.
Though the south corridor extension is shown as engineering in the status column, construction is underway on parts of the extension, the two bridges, and will start soon on other parts, with the help of a recent federal grant as well as regional funds. The airport extension and streetcar projects also have their own webpages.
Most of the other projects link to the Sacramento TransitAction Plan, which show all possible projects in Scenario C (map at right, more detail in the plan starting on page 50). This plan does not give much detail on each project, but the name of the project gives you an idea.