At the start of August I'll be in Sweden for two weeks (middle of nowhere, really. "Skillingaryd"). I would very much like to have some internet there… I was considering buying a Swedish prepaid SIM card with data, but I have no idea about what to buy, where to buy it, etc.

Can anyone make some suggestions? I'm open to other options as well.

Thanks

If you have a mobile that you can use in Europe and easily can use as a WiFI accesspoint I would buy a Kontantkort (SIM card) from 3 that mostly have the best speed.
You can buy it from many petrol stations and bigger supermarkets.

If you don't have nessesary hardware just go to one of the phone shops in the town.
Phonehouse, Telia, 3

Here is e.g. the offer from 3
http://translate.google.com/translate?sl=sv&tl=en&js=n&prev=_t&hl=sv&ie=UTF-8&layout=2&eotf=1&u=http%3A%2F%2Fwww.tre.se%2FPrivat%2FMobilt-bredband%2FDataPrepaidPage%2F

If you mainly will stay at one place during your visit and it's in the middle of nowhere, check with any locals before just to be sure the operator have a good cover.