Sony PRS-T1
Hi man, I've ordered a PRS-T1 from a cousin of mine who's coming to Pak in a couple weeks from the UK. The thing is costing around 130 pounds (inc. VAT, which is prolly refundable; not sure how that works).
If you know someone who is coming from the US, that would probably be your best bet though.
I was thinking about getting the Nook Simple Touch, but since it's not easily available in the UK, I've gone with the Sony. Check it out. I think it's currently the lightest ereader on the market, and also one of the thinnest. It can view RSS feed formats as well, which the Nook doesn't have. It also has audio output, which the Nook doesn't have (but this wasn't a big selling point for me, since I use either my phone or iPod shuffle for audio).
I definitely recommend checking it out. Regardless, both the Nook and Sony ereaders are solid choices. I would steer clear from the Kindle. It's not as responsive or as fast as these other two. Plus Amazon locks you into their stupid marketplace. I'm sure there's a workaround for that, but why even bother going through the hassle?
Just my two cents. Good luck with your decision.