Cache Valley Hikers: A local group that meets from spring through fall to do various hikes, mostly in Logan Canyon and on the weekends. They post their upcoming events on the Logan Library Events Calendar.
NewComers: Has a hiking interest group.
There is no comprehensive resource for hikes or trails in the area. Cache Trails by Jim Sinclair is the closest. It is not avialable for sale online, but is in local outdoor stores. I have the 2004 edition (rev 2006). I haven't seen any newer versions. A 1994 edition is posted online. It lists Jim Wood as the author, but has a similar structure and the same publisher. There are notable differences between the two, so it's worth looking at both. The online version focuses more on the trails and provides notes on how to put them together. The book focuses more on recommended hikes and frequently joins several trails together, sometimes piecing them together with fire roads.
The Logan Ranger Station is working on a list of local hikes, but it doesn't include much descriptive information. It does give information about what type of access is allowed (horses, bikes, ATVs, etc) and the seasons that the trail is open. The visitor's bureau lists some city hikes that aren't elsewhere.
In DC/Arlington, there were only a couple of "hiking" trails within half an hour of the city. So I'm used to driving over an hour for a good hike. Most of the hiking information above is geared toward hikes right in the Logan area. If someone was looking to explore futher there are trails available off Hwy 36 between Preston and Montpelier, ID. This area has Cache National Forest signs, but there US Forest Service map online shows the boundary at the UT/ID border. Cache Trails shows some trails into the Idaho border including Danish Pass and Sink Hollow. In any case, the proximity of the Logan Canyon hikes makes it tempting to stay local.