How to arrange meetups
While the ideal of geohashing requires no more organization than people knowing the day's coordinates, real life meetups may require a little more planning. Whether you need a ride, want people to wait for you, or simply need the reassurance that you aren't the only person from the Internet who will be venturing into your graticule today, sometimes you need more than a latitude and a longitude before you head out the door.
There are several places to look for meetups being organized. Check as many as you can, because different people and graticules do things differently. Likewise, make it easy for new or visiting geohashers to find out your plans.
In truth, most geohashing expeditions are not substantially arranged in advance. You know the place, you figure out how to get there and you go. That's why it's a spontaneous adventure generator. But if there are plans, and geohashers are encouraged to make plans, even as simple as "I'll try to get there!" the plans will probably be in one of these places.
First places to look
A newcomer to a graticule may be able to find out expedition plans from these places. Experienced geohashers should try to make that possible.
Current events page
All expeditions with a planning page including date and location categories are automatically listed in Geohashing:Current events. There is about a ten minute delay before expeditions turn up there, and not every planned expedition has a page, so also check some of these other places.
Graticule pages and Graticule talk pages
Meetups are often announced on graticule talk pages, usually under a subheading matching the date of the meetup. Click the discussion tab at the top of a graticule page to find its talk page. This is probably the best place to announce possible meetups, because it is easy to find, doesn't clutter the aesthetics of the main graticule page, and doesn't require anyone to make a new page. If discussion is going on somewhere else, make it easy for new geohashers to find it by linking to the discussion from the graticule talk page. You should select watch this page for your graticule talk page so you know what is going on. Once anyone decides to go, an expedition page should be created.
Some graticules, e.g. Portland, Oregon, announce meetups right on the front page of the graticule page. Avoid entries like 2009-04-23 - Corner of State and Main Streets next to a tree that do not make it clear whether you are just cataloguing or really planning on attending.
Meetup pages and Meetup talk pages
If a meetup requires a lot of coordination or pre-planning, it's useful to discuss it on the page for the actual meetup. That's the page that peeron offers you the opportunity to edit if you click on the Meetup link in the bottom left after you have selected your graticule. Its name is of the form YYYY-MM-DD LAT LONG and it is the page where the completed expedition report will appear. Sometime the discussion is on the Meetup page and sometimes on the talk page, behind the discussion tab. Wherever the discussion is, it should be linked from the graticule talk page. This page will automatically be summarized on the Current events page.
An active graticule can have other ways to announce meetups.
E-mail this user
If there are geohashers listed in the graticule, but no one appears to be discussing a meetup, you could try e-mailing someone. Visit their user page (click on the person's name) and then fill in the edit form.
Geohashing IRC channel
Sometimes wiki editing is an awkward way to discuss things, so people use the Geohashing IRC channel for real time chat. If you are discussing a meetup on IRC, please, please also mention it on the wiki, even if it's just "2009-05-24 meetup currently being discussed on IRC".
The peeron application allows you to designate and vote on an [[[Using the Coordinate Calculator#Alternate Meetup Locations|alternate location]]]. It's a functionality that isn't used very often and many people get their coordinates through other means, and thus will never see your suggestion.
Some graticules have Facebook groups, but not all the graticules that have them use them. It's worth joining if you use Facebook anyway, but don't count on being notified of meetups that way.
There may be a mailing list for your graticule. Check the graticule page for information on it, or any other ways they may have of propagating information about geohashes.
Sometimes the discussion about going to a geohash starts in a comment on someone's userpage. Geohashers should move such discussions to the graticule talk page or meetup page as soon as possible so that new users have a chance to see it.
Even if no one has announced an intention to go, and no one responds to your intent to geohash, you should still go if the location looks interesting. Some geohashers never read the wiki, just look up the coordinates and go, and it is fun to meet them.
Remember that if your longitude is less than -30 (30W), that weekday coordinates will not be available until shortly after 9:30 a.m., U.S. Eastern Time, so there is unlikely to be any conversation about a meetup before then.