For just a decent Friday thru Sunday trip, there is a pretty good place up at Harry O's/Les Hilde up at Hamilton.
Kalama Horse camp as mentioned is another one to venture off to.
Keenes Horse camp near Randle should be on your short list of places to go too.
Eastside:
Twisp River horse camp is one of my favorites. Steer clear of the major holiday weekends here, particularly the 4th of July weekend. Methow BCH has a big shindig there that weekend and it takes up the whole horse camp.
Beaver Creek near Twisp is very good. Go early as it can get to be a bit challenging with the rattlers as it warms up.
Same with Burke Lake over at Quincy (rattlers).
Haney Meadow/Ken Wilcox horse camp is still shut down due to the Table Mountain fire. It was great before the fire - you missed out on one of the better places to ride but it will be good again from a scenic standpoint soon enough.
The old Tamarack Springs horse camp on Manastash ridge is a pretty good place to go.
Blackpine up the Icicle out of Leavenworth is pretty good.
Chiwawa River horse camp - don't bother - no trail maintenance done in many years.
Phelps farther up the Chiwawa is worthy of visiting.
Mount Adams horse camp is another must go at least once place. You'll probably go back even more.
Conrad Meadows is good but your horses must be in tip top shape and very experienced riders only.
Cayuse horse camp near Salmon la Sac is another good one.
Or, you can just skip the horse camps where you can go be by yourselves like we primarilly do and just head up into the LT Murray, Wenas or the Colockum - grab any 'ole hunting camp and toss the high line up and ride game trails.
And, if you need more info, the Capital Chapter of the BCH has put together a nice list and links for horse camp / horse camping stuff......
http://capitolriders.org/gps.htmDon't forget about the certified weed free eats for the horses on NF land. Not a worry on DNR or WDFW lands.