Since you are starting early into the RTS world, I suggest first picking up a copy of Command and Conquer: Last Decade, all original 12 command and conquer games (including expansions) to start at the basic building blocks with C&C1 and continue to build all the way to C&C:G:ZH. At $40 its a STEAL! Having all original copies, still got it because of all the games on 1 DVD, super convienient!
Second, I would pick up a copy of either Dawn of War Platnium (Dawn of War, Winter Assault, Dark Crusade), Company of Heros, or Command and Conquer 3. Building up the way new RTS are (way easier then old RTS, you'll see if you are playing the older C&Cs).
Third, I don't suggest, I DEMAND YOU (lawl) to get a copy of Starcraft. One of the most simple and challanging RTS games out there, if you can pwn at starcraft, then you are good to go for all other RTS.
Hope this helps.
Erm ... I didn't say I was new to the RTS world. On the other end of the spectrum, actually. I wrote some of the ZH guides for PP, too.
But yeah, some more on my request would be nice, ty rugmonkey.
Edited by Hellswarm, 14 September 2009 - 06:56 PM.