I'm working on the kernel version Linux-2.6.29-rc5 with U-Boot 1.2.0-g88e21e7b-dirty.

I recommend you use a more current version of U-Boot. That one is quite old.

Does the flash node HAVE to be within a localbus node or can it reside within the soc node? I've been basing my work on mpc834x_mds.dts
And hence haven't defined a localbus node.

I think it can be in either, but the most common place I've seen is in the soc node.

BTW is there a way to search the ML archive? Currently I browse each month to search for prior postings.

Yes, Google "site:ozlabs.org <what ever you are looking for>"

Mike