In Mountain Lion, you can use the Resume feature to achieve that.
First, go to
> System Preferences > General
and uncheck the box called "Close windows when quitting an application".
Second, click the power button once to bring up the logout window. Check the button that says 'Reopen windows when logging back in'.
Press 'escape' to dismiss the box if you don't wish to restart/shutdown at the time (OS X will remember the setting even after you escape it until you change it again in the logout window).
Yes, you can do it in Automator but it's just not the most efficient way of doing it. The OS 'application savedstate' feature (which you turn on by the instructions I gave you earlier) should do that without 'bugs'. I'm not sure what you mean by 'is buggy', but that sounds like an unrelated issue. It works fine on my system and every system I've ever done support on.
In any case, if you insist on using Automator, you need to create a new workflow, and then do a separate 'watch me do' recording for each app. If you've got 5 apps, you'll want 5 recordings that play one after the other in the same workflow. Don't try to record the whole set up in one 'watch me do', it'll never work.
Test each recording by hitting 'run' before making the next one. It often takes a couple of goes to get the recording to work flawlessly (unlike 'application savedstate', this feature is 'buggy'), and you need to click apps from in the Dock and take it slow, or the recording won't pick everything up.
Hunt around youtube for 'automator' and 'watch me do' videos if you need a visual demonstration, but its fairly intuitive. Just don't get frustrated if the first couple of recordings throw a "the action 'watch me do' encountered an error" message. The trick is to make shorter recordings with a small number of actions in each one, and then string them together in the same workflow.
The reason I was thinking Automater would work better for me is because of the addon/plugins that I run in all of my FireFox/Chrome windows. They're all custom build and the browsers require a complete quit and reopen every day or two. With the savestate I am still having to drag and place everything every few days.