Ive been shooting for a year now and have used the old digital rebel 300d for all my shoots.
Wondering if I should either:
Just get another Rebel when it dies
or
upgrade but if I upgrade actually go a step above a 30d and get like a 5d or a 1ds

???

I think you will be just fine with the 30D.

rephrase

i meant instead of getting a camera in that range of the 20d, 30d, rebel xt, just get another digital rebel
or if i upgrade, would actually upgrade to a higher end camera then those

Is there something specific pushing you to upgrade? Something that the 5D or 1Ds has that you want/need?

If you are happy with the Rebel and just want to upgrade 'because' (we all get gear fever) maybe consider the new Rebel model (Rebel XTi)... it seems like a significant upgrade to what you have for $100 less.

The answer to your question depends on so many things that what you are going to get here are nothing more than educated guesses.

1DS only if you truly need speed (like you're a sports shooter)
5D only if you need and understand full-frame
otherwise 30D

forget getting another rebel unless you're still unsure if you want to shoot or unsure if you want to shoot digital.

My motto is "shoot until you grow past your gears abilities, then upgrade.  Rinse and repeat"

If you don't feel limited by the controls of the rebel, IMO there's no reason to upgrade.  If you do upgrade, I think the 1D series is a little overkill for modelling portraits unless you're pretty darn serious.  The 5D is nice for having a full frame sensor at a midrange price, though some like the extra reach of a crop sensor without having to shell out for big glass.

I believe one should only buy what they need, don't spend more money because everyone says it's better.  The features that make it better may not be that important nor worth the extra cost to you.

Full frame would be ideal reason

just would grab another rebel for cheap verse a 30d because doesnt really matter because if you cant shoot you cant shoot forget the camera

Speaking as one who shot with a 300D for a couple of years, I really loved the camera and think I did some really good work with it.  This year, I decided to upgrade.  A photog friend here in Tyler has been using a 20D for a couple of years and I really liked his camera, but decided to skip to the next level as I kinda missed full frame.  So, I bought a 5D.  I put a lot of thought into that decision and looked at the positives and negatives of each camera. The XT was out immediately because of the smaller body.  The 300D was about the right size and I really hated to see Canon downsize it.  I looked at the speed of the 20D and it would be nice to have, but I don't need it all the time and I was already used to the speed of the 300D.  I was really attracted to the larger LCD on the 5D.  Anyway, it all boils down to looking at what you want and what you will need in the future.  I am totally happy with my purchase and the brighter viewfinder allows me a better chance to get things in focus when I am using an EF lens in manual mode or when I am using one of my manual focus lenses.  (Nikon glass is the ~!@#, by the way get some adapters and find out for yourself.)

I've been using a 350D, and, after learning the difference between shutter and aperture back in june, i've wanted a 30D ever since.

but the nice thing about the 350D is its size, because i bring it everywhere.  If i ever get a camera with manual dials and alloy construction, i'd still be  using my 350 for random adventures.

I'd wait a little bit..

If your budget is unlimited and your biceps are beefy, can't go wrong with the high end, obviously..

If you're a mere mortal and not doing sports shooting it seems like the choices are between the 5D - full frame, 12mp - and the just released XTi - 10mp, crop...

From personal experience I'd go after the 5D..  It's a pretty wonderful camera all around..  But right now an XTi and a grip is going to match a 30D on most levels and surpass it on one or two..

But just being released.. Like I say.. Wait a month.. Get reviews..  Wait for early adopters to find bugs..  RAW converters to be released.. And so on..

If your budget is tight, I'd wait for the new Digital Rebel, the XTi, and go for that. It should be out soon. Looks like it will be a nice upgrade since Canon will have to compete with the new Nikon and Sony 10MP units.

I like the old Digital Rebel and still use it a lot. In some respects, I prefer it over my old 10D.

The Rebel XT is an upgrade, but my XT had a strong magenta color cast I  had to set the color balance manually to correct it. Once that was fixed, the XT was a fine camera.

If your budget is unlimited, then just get the best you can afford.