Which DSLR for £350 max?

I'm new to 'proper' photography, and am wondering what to buy for my first DSLR. I want to spend a maximum of £350.
I'm interested in going into a photography career. I'm 16, living in the UK. I'm just about to start my AS Levels, but if I'm still interested in photography, I will do a course at my local college.
I'm looking at getting either the Nikon D3000, Canon 1000d, Canon 1100d (If I can afford it!) or Canon 450d.
What should I get? Or is there a different one I should get for a similar price?

That's about $570US and the only Canon cameras available at that price are the 1000D and the
1100D. The 1100D does 720 HD video, the 1000D does not (I know because I own a 1000D) It's an excellent camera but no video.

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