Actually I would suggest to work the other way around, first make your guild on paper. Create the concept, think about what makes them unique, what your guild has to offer to the community, etc. Write up a guild history, ranks and maybe even start on a website.
If you want some good examples just take a look in the Guilds section of these forums.
As soon as you have worked all that out it will be a lot easier to create your guild in-game so all you still have to do is find some members to start your guild with.