Well, it's always a good thing to save money......but,
I would still really like to know if there are computers that are already packaged (such as an XPS) that are strong enough to run Oblivion maxed out.
I know that custom built is the way to go, but aren't there any commercial packages, though more expensive, that are comparable? I'm always up for doing upgrades myself, but I'd like a well-supported base system with warranty and such.
So, any links to these types of computers that are pre-built, but still kick-ass? I always read things about awesome computers, blazing specs etc, but I'd be interested in seeing people's real-life experiences, especially with Oblivion in mind. (Back to my initial question, ha)

Well, it really is dependent on the amount you wish to spend. You can get warranties at any PC customization site, so that's a non-issue. However, the XPS isn't exactly the best option since they tend to be overpriced far too much. If you want an excellent gaming rig, customize at one of these places and pick up a warranty there:
http://vigorgaming.com/
http://www.buyxg.com/
....If you need help choosing parts, then open up a new thread (so not to clutter this one) and indicate:
1.) your budget in your country's currency
2.) what country you reside if not listed in your avatar area
3.) pre-assembled PC? ...or can you build your own?
4.) what is needed other than the PC tower? Monitor, speakers, mouse, keyboard, Windows OS disc? All these can jack up the price.