How to check how much battery the data network is using?
A bit of a hack, inconvenient and I'm not even sure if it would work: Download Juice Defender, set it to always keep data disabled and later check how much battery it claims to have saved you.

As for the Wifi, on my Phone (Xperia Neo V, 2.3.?), it's a separate entry on the battery usage panel. Maybe you used it so little that it isn't even displayed (probably &lt;0.5%)?