I previously wrote an article on how to get Casey's tactics manual onto your Blackberry. Here's a list of field manuals used during the Civil War. Let me know if there's anything you want me to add to the list.
Google Books also lets you download pdf and epub files. Mobipocket files are for the Mobipocket Reader for your Blackberry or other smart phone.
Update: Google Books doesn't let you download pdf's any more. However, they do offer an app that's available for all major smartphones and tablets. I've kept the links to epub and mobipocket for legacy devices.
There's also a demonstration of Hardee's using Lego men. I highly recommend this excellent resource.
For more information, you can read an overview of the tactics manuals.