Yesterday Reuters reported that gadget prices fell by 0.8 percent in January compared with retail prices in December 2004. Apparently NPD produces a statistic called NPD Consumer Electronics Price Watch which tracks a market basket of the "27 most popular electronics goods". Reuters apparently considers the NPD Consumer Electronics Price Watch a sort of a gadget price index.
According to the article, desktop computers and hard drive prices fell while DVD players and tape-based digital video camera prices increased.
I'm surprised that there aren't more indexes like this with greater transparency in how they are computed.