What is a general strategy for someone new to Dawn of War?

I will begin this question with the following disclaimer:

I am absolutely terrible at RTS games.

With that in mind, I am hoping that a simple, general strategy may be proposed for a noob player that really does not want to get deeply involved in learning the ins and outs of each class...I do not plan on going through the single player or learning enough to professionally compete, this is more knowledge for the person who will play this game a few times within the course of the year.

That being said, I am going to be doing some LAN gaming soon and this is one of the games we will play. The last time we played I got absolutely creamed and would like to at least put up a decent fight.

I have no race preference...really whatever is the easiest to get up and running and put on a good showing is what I would prefer. We have all of the expansions, so the extra races are available as well.

I think the general rule of one strategy per answer would be appropriate here as well.

I'm far from an expert on Dawn of War, but since no one else is answering, here goes...

For a new player, the Space Marines are probably the easiest to learn. They don't have any unique game mechanics to master (like the Necrons' power-but-no-requisition or the Orks' WAAAGH!), and they don't depend as much on micromanaged special abilities and carefully balanced unit mixtures (like the Eldar or Imperial Guard).

Try the following (approximate) order:

1. Queue a couple of Scout Troopers and a Servitor. As soon as the Scout Troopers are done, send them to start capturing strategic points. Queue up a couple of strategic points each to keep them busy.
2. Set one Servitor to work on a Chapel-Barracks and the other on a Power Plant. Send whichever one is available to build Listening Posts once your scouts have finished capturing strategic points. A listening post costs 100 req, but once it's complete, you immediately gain 50 req, so it's cheaper than it appears, and they're critical in the long term for a good economy.
3. Set your Chapel-Barracks to build a squad of Space Marines and the Force Commander. Attach the commander to the space marine squad. Reinforce the squad. Build a second squad if resources permit.
4. Use your space marines + commander to harass the enemy or defend your base. Use your scouts to de-capture any strategic points that they've left undefended.
5. Next, it's time to advance to the next tier: upgrade your Stronghold to a Monastery, and build an Armory.
6. Now the fun starts. Research Heavy Weapon Increase at the armoury, and outfit all of your space marine squads with the appropriate weaponry: plasma guns for heavy infantry opponents like Necrons and Space Marines, heavy bolters for infantry like Eldar, and missile launchers for buildings and vehicles.
7. Build Gray Knights and attach the Chaplain for an easy quick-hitting melee unit.
8. To keep the gameplay even simpler, you can postpone building the Machine Cult and focus on the Sacred Artifact instead. Using one exclusively probably isn't an optimal strategy, but it lets you stay focused on infantry instead of having to juggle vehicles as well.

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