ibook shut off after re-installing OS, now it won't turn on

I bought an ibook a little while ago because I wanted a small, simple notebook and I love my home iMac. I found one for a good price on eBay and when it arrived everything seemed ok. I wanted to re-install the OS and set everything to my specifications because I was having a little trouble with some of the apps. Anyway, I went through the lengthy re-install and just as it finished counting down the seconds to completion, it shut down. I thought it might be in sleep mode because the little white light was on, so I hit a key and the light went off but nothing happened. Nothing on the screen, no HD noise, nothing. I'm at a loss because I really don't know much at all about hardware or software, which is why I liked the user-friendly Mac so much. The only thing that tells me it's getting power is the little green light at the power connector. I tried a PMU reset (there's no reset button on my model so it was a button combo of shift-ctrl-option-power I think) but that didn't do anything. I'm hoping it's not a logic board issue because I think that's a rather expensive fix if I'm not mistaken. If anyone has any info about what the problem might be or a possible fix, I'd be really grateful.
Thanks,
-Jeff

Leave it plugged in overnight, it might help. Otherwise it does sound more like the beginnings of a failed logic board. Has similar problems to a 14" that I was given and since gutted.