hunting down computer lock-ups in console

[Corrosive vinyl]

I have been trying to fix an issue with my ibook locking up seemingly at random times. my system.log has a few errors, such as:
1. kernel[0]: I2CUserClient::read cannot read from I2C!!
2. Server 0 in bootstrap 1103 uid 0: "/usr/sbin/lookupd"[138]: exited abnormally: Hangup
3. Sound assertion "0 != err" failed in "AppleLegacyAudio/AppleTexas2Audio/AppleTexas2Audio.cpp" at line 960 goto Exit

I think there is an issue with the lookupd which I have researched on the web, but I am worried about the other issues and wondering if there is a painless way of fixing them. I have no idea what I2CUserClient is and don't understand why my sound is freaking out. Any advice would be appreciated.

I just recently installed a new HDD and memory.

 

[angelwatt]

I generally just take snippets from the logs and head to Google and follow any breadcrumbs I find. I can generally find others who have had the same error, but it can take longer to find someone who found a solution to the error. Just takes some patience and persistence.