This little NAS from Aria seems perfect for your needs
http://www.aria.co.u...productId=49178
You'll need to add drives to it but it supports RAID 1 with 2 drives, uses ethernet, supports remote file access and has some other features you may or may not use in future.
All for £160 (including drives).
EDIT: Actually more like £180, forgot you lose a drive in RAID 1, still cheaper than the WD My Book and the LG NAS can only be found in 1TB at reputable UK retailers, 2TB on ebay and other unfamiliar sites.