Having just purchased my first DSLR (not received yet) I can offer a bit of insight into my own thought processes. I won't pretend to be able to answer questions on technicalities, compare cameras and so on, just the way I approached the same task.
First choice
New, used or refurb.
New: Never been used or handled, full warranty, no quibbles from the seller and no fear/fuss. You will get a good camera. However, the camera you get will be more expensive or of a lower spec.
Used: Get a better camera for the same money, possibly get one or two odds and sods thrown in for the price (memory card etc). But, you don't get a warranty and as with anything
second hand you take a risk.
Refurb: Combination of the above. You get a warranty, but still run a small risk that there might be an underlying issue. You make quite a saving on the new price.
After lots of thinking I plumbed for a refurb from the
Canon reseller on ebay. I don't have an opinion on the camera yet, it hasn't arrived (only purchased yesterday).
I went for the 400D, but you mentioned the 1000D. Well, a quick look through the sellers feedback reveals the following.
Of the past 500 feedbacks received, 12 were for sales of the following.
1000D with 18-55 IS refurbished
They sold for:
Min £250
Max £336
There was also a 1000D sold with a 55-200 lens in addition and that went for £360
So, figure that if you decide to go for a refurb, and you don't need it now now now, then a bit of patience and you could probably get one for around 270.
The key to it, just wait till the seller is selling 1000D's (currently on 400D as I said) and then just visit the site every day and add to your "watching" area. Place a bid on the ending soonest one of 270. If you get it, great. As soon as you are outbid, go to the next one, place a bid of 270. Repeat.
It amazes me that people bid 330 for stuff like this when all they have to do is go to the feedback and see that the same item goes for much less, but meh, each to their own. It took me 7 items to eventually get the camera, though I also received a second chance offer on one that I had been outbid on.
As for camera comparisons, best site I found was dpreview, not sure if we are allowed to link to stuff like that here, but there it is.
Should note, the refurbs from that reseller come with a 1 year warranty, not sure how to use it yet, but that was the clincher for me.
If only I knew then what I know now, then I wouldn't have bought my 1000D and outgrown it so fast. 
:shrug:
