My first suggestion doesn't have anything to do with recruiting, per se, but here goes:
Make sure you have the leadership, structure, rules, and goals firmly in place and laid out for everyone to see/acknowledge, especially new recruits. Trying to attract the right kinds of people to your guild will be hard enough to begin with, but you need to have the ship running smoothly in order to make a good first impression with recruits. Filling out your roster will go to naught if you're not organized and provide the new recruits with what they're looking for in a guild. If you want to raid, then you better have a good raid leader, strats worked out, etc. to show recruits you guys are up to the task.
Also, Here's a recent WoW Insider article on finding a guild. There may be some useful ideas you can use (reverse engineering) to help you recruit.