Post the model!

The software recommendation is highly dependent on the brand/model.
This is more on the high end consumer/pro side but Canon includes software for their DSLR line that allows interval shooting. I don't know if it extends to the point and shoots. Nikon has something similar as well I believe.
Lightroom 3 has support for both companies' DSLRs with tethered shooting.
Unless you ordered a model with a specific time lapse mode, you will still need a USB connection. You can get a USB extension cable from Monoprice.com for < $10. I've shot tethered with my Canon Rebel T1i using 4 USB extension cables strung together with no problems. (Total length was 20ish ft maybe?)