Thank you for the link and advice.

The only reason I wanted the i7, I suppose, is because I want to keep the computer for as long as possible before it's completely obsolete...And without worrying too much about upgrades along the way. So getting a high-end processor seemed a good idea.

Thanks for directing me to e-Bay, I didn't even consider that as a good place to buy a new computer... (Though I did buy a "laptop" Tandy there once for $25

). There's a whole bunch of options similar to what you've linked to on eBay Canada at similar prices, so it seems like an option... But the savings actually don't seem
that big once you add it all up. In addition to a graphics card, for most of these options I'd also have to buy the operating system separately (though I guess you can find it at a discount), and then there's shipping for everything... It still works out cheaper, of course. I'll have to try adding up the costs and think about whether it's worth it -- still, thank you for the option.

Certainly putting in a graphics card sounds a lot easier than assembling the whole thing from scratch.
Also thank you Spinoza, those are good lists of components to look through... No pre-built systems since 1988? :S It's like no-one aside form me (and Mr. C., it seems) buys pre-built computers at all any-more...
Honestly, though, one thing that strikes me is that pre-built systems don't seem...
that much more expensive? I mean, there's a difference, yes, but, well, let's compare: On the previous page, germloucks' list, for example, has $1,106.00 for components that include: an i7 2600k, 4 GB DDR3 RAM, a GeForce GTX 560, a 1 TB HD, all the stuff you plug this into, and the other odds and ends. This price does not include taxes and shipping.
Now I'm comparing this with Dell, which is where I'm still thinking I'll probably buy my pre-built system, unless I decide to go with turtle's eBay suggestion. One of the, uh, comparatively "less expensive" options I'm looking at comes in at $1,237.98 before tax (no shipping fees). (Now, normally it costs more like $1,500 -- the price is a discount. Then again, Dell often has various discounts.

Either way, $1,237.98 + tax is what I'll be paying for it if I decide to get it!) This includes: an i7 2600 (no K, but I'm not going to be overclocking anything

), 8 GB DDR3 RAM, AMD Radeon HD 6870, a 1 TB HD; other odds and ends (2 USB 3.0 ports, the operating system, and, uh, the latest version of Microsoft Office, because it seems I'm behind one. >_<). Admittedly, the graphics card is a small step down from the GTX 560, judging from
this, and I assume it doesn't have a "OCZ Solid 3 SLD3-25SAT3-60G 2.5 60GB SATA III MLC" boot drive... I don't know what that is! It sounds important. Argh. But anyway. Basically, it's a...
I think, it's a comparable system (well, presumably a little worse, but... hopefully not downright terrible in comparison?) for what probably works out to be roughly the same price (especially once you consider no shipping fees and the OS is included). Obviously it's not going to be quite as good a deal, but... It doesn't seem like that
huge a difference, is what I'm saying, especially if I'm willing to pay a premium to save myself from having to assemble the system...
So... I am guessing that those who build their own systems really do it for the joy of it, yes, at least in part? The savings, while present, seem to be not
huge enough to warrant the additional hassle unless it's something you really enjoy...
Of course, I don't really know what I'm talking about in the end. And even if I do get a pre-built, I still do appreciate all the advice I've gotten; I'm actually really surprised -- I didn't expect so many responses from so many people, with obvious effort going into the replies, too. I really appreciate it, and I don't want to seem ungrateful if I don't end up taking the advice in the end -- it did help me figure out what I should be aiming for, I think...