Open Question: Camping in montana (start from bitterroot vally)?

ok so this spring me and some friends are going camping, one person suggested "lost horse" but i dont know where that is so i know nothing about it

what i want is a inexpencive (free if possible) camping area near some good trails and mabye near lake, or other suggestions would be great, we need some excitment and exploring

(if you give a suggestion then tell me how to get there i need directions)

Source:
http://answers.yahoo.com/question/index?qid=20110328193808AAJNrW1

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