Can I buy a smartphone and just use it at Wi-Fi hotspots without signing up for a plan?

If you want to use it as a phone… I don’t think so because the carrier still has to assign you a phone number to use (regardless of the network you are using.. wifi etc) which would require a plan.

If you just want to use it for data features mobile web surfing..you can but you would have to buy it at full price or find someone selling on on craigslist. Tablets are another option, I have the samsung galaxy tab that I just use on Wifi and I love it (but again you don’t get the phone with it its just data)

You could but you’d be better off getting an iPod touch.

Like @Lightlyseared and @mrlaconic said – and you yourself seem to recognise – you’re barking up the wrong tree.

Either an iPod Touch or some kind of tablet PC would be far more appropriate. With the tablet PC, you can always add a SIM later should you recognise that your needs have changed.

There’s the Nokia N800. It’s smartphone sized and has Skype in case you need to make a voice call.

Thanks for your suggestions! You’ve pointed out some options I wasn’t aware of.