The canyon called Okhtangi where several comps are located. The prices of the camps diverse.From northern part you can go there from Khujand by taking taxi that should cost ~40$ per car.
The distance from Khujand to Okhtangi is about 120 km. If you are single than you can take shared taxi to Shahristan (10$) and then taxi to Okhtangi (~10$)
From Dushanbe you can also take taxi directly to Okhtangi or shared taxi to Khujand ( 20$ per person)and take out in the entrance of canyon and then 15 km by walk.
The lake Oykul is the final destination of majority hikers. It takes from 3 to 5 hours to reach this lake which is 3108m above sea level.
I marked camps with red X and the lake with red circle on the map. More maps can be downloaded here http://loadmap.net/en/m19349.
There are several antennas of main mobile companies there (Tcell, Babilon-M, Megafon).
So, you can use mobile services and internet (3G) almost everywhere in Okhtangi.
On map you can see that there are many peaks for climbing. The nearest and highest peak is Kurganak 4057m.
Shahristan is very historical place which was capital city of the Oshrusana between the 6th and 9th Centuries AD. You can find an ancient wall paintings in the cave, ruins and etc. More info here: http://whc.unesco.org/en/tentativelists/1387/
Recently, I found out that there is ruins (before ancient) in Okhtangi that was in front of camp where i usually stay. Two years ago, several German archeologists conducted excavations there. And locals who where there told me that they found (germans) a graveyard of that village where skeleton of those people were larger than ours. You can see some bones on the edge of caves.... Also, those archeologist collected piece of meteorite rock from mountains and alloyed them in order to see the metal consistency.
Unfortunately, I couldn't find any information about their expedition on internet