You can get CS4 for an extremely low price using the teaching or student discount, around £250 I think. The older ones can be bought on amazon on the likes for a cheaper price :-)
I'm taking a look at Caboose's suggestion, it was #2 on the Gadget Show, so can't be that bad...
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Photoshop Elements 7 is only $90, and does most of what CS4 does (I have it only an old mac, it runs well on old computer)
Absolutely not, Elements seems a pretty comprehensive and powerful piece of kit until you get CS4, then it's weak. It is barely even comparable, it's more just an entry-level photography editor than a graphics programme, though it's still an excellent product.
Edit: Thanks
