Well, you might want to clarify exactly what type of tactics you are talking about. Do you mean squad level, company level, divison level, et. al? I assume that you mean small-scale tactics, such as squad and platoon level tactics, since that is really what OFP is designed for. In that case, newspapers aren't really going to be much of a help, since they cover large-scale troop movements. What I would suggest is a really handy book called the Guidebook for Marines. It has tons of useful information for marines on topics such as drill, mc history, weapons maintainence, close combat, land navigation, defensive constructions, combat formations, hand signals, etc. The part that would most interest you is the chapter on squad tactics. It pretty much has more information then you could put into a mission. You also may be interested in learning about marine corps unit structure, such as MAGTF's, MEU's, etc.
The Guidebook for Marines is published by the Marine Corps Association in Quantico, Virginia. I got mine at the PX in MCRD, San Diego. I'm not really sure where/how you could get a copy. If there is an MC unit stationed nearby you, you could get a copy at their PX. You might be able to order it online or something, too. There isn't a website listed in my copy, but there is a "bookservice" phone number, which might be of use: 1-888-237-7683