I think you are probably beter off working within the two existing parties than trying to start a third party. The third party won't win and the in meantime, you just draw off votes from the people who are most closely your allies.
No offense, but this is a very shallow statement. You're saying not to pick the best person for the job but pick one of the two that you hate the least.
There are other voting methods that would allow for a third party candidate to make it into office. I'm unsure as to what it's called, but essentially it doesn't deal with an absolute candidate. You vote for all of the candidates on the bill that you believe would suit the job. So you can vote for the democratic or republican candidate and still vote for whatever third party you want as well. For that matter you can also vote both republican and democrat if you feel that both would be well suited for the job. After all is said and done, then the votes are tallied and then you have who the people would really like to have in office. This way if you want a libertarian candidate in office but don't want a republican in office you don't have to pull your vote away from the democratic party to vote libertarian, you can vote for both.. and then in the event of a tie then you have a run off of the two (or whatever number) of candidates that are tied.
If people weren't so afraid of "wasting" their vote, more people would vote for the right candidates. But here's the thing to remember.. if you are worrying about "wasting" your vote, it's no more of a waste to vote for who you really want than it is to vote for the lesser of two evils and still lose.