[Recontech]

Should I go the more inexpensive route and get an external HD and just connect it via USB? Or, should I get a NAS? And what NAS to get that is compatible and easy to mount via OS X?

I need more space for iPhoto library...amongs other things.

[cgc]

If you can't get another internal drive I'd opt for an external case with FireWire 800 (or 400) and skip USB altogether. NAS is only useful IMO if you have a network.

[Frugle]

I have a huge USB tree of USB external enclosures and all of them work great...

I hate how the 1st gen MBP did not have FW800, so I don't have any 800 drives.. but I know eSATA is very effective and you can get an express34 eSATA card pretty cheap now.

[Recontech]

I was thinking a simple WD Mybook would be a good solution. But, I figured that I could externalize my iPhoto library and just keep it all on the network.

[-Q-]

Unless you have a couple computers on the network that would need access to the drive, or want to use a centralized backup solution for those computers on your network, I don't really see the need for the expense of a NAS-system quite yet. I've tried a Linksys NAS and didn't find it too reliable at all (the drive attached would just stop appearing on the network). I think your WD MyBook idea would work perfectly for your needs.

[mduell]

It's only about a $20-25 difference to add ethernet... if you have any reason to put the storage on the network (multiple computers, laptop with wireless, etc) I'd go with NAS.