Your best bet is to look at a site like visajourney, looking for TNers who married USC's.
First off, now that you are a 'fiancee' you need to be careful crossing the border so as not to let this be known, as even this will be considered sufficient to disallow you entry on TN (and make you wait outside US for a fiancee visa). So be discreet.
Assumimg you want to continually work during this period, the steps are (in as much detail as I'm going to give):
1. You must have at least 5 months left on your TN AND you should not have renewed or crossed the border in TN status for at leat 45 days when you submit your papers. So plan for 6 months left in TN and 6 months staying put in US.
2. Get married in US and honeymoon in US (you can't leave US during any of this period).
3. File I-130/I-485/I-131(AP)/I-765(EAD) all at same time, following the current filing procedures. Your TN remains valid, but can't be used to enter the US. Therefore you need to migrate to EAD to work (which will take 2-3 months) and need the AP to leave US (which could take longer). So plan to be in US for 4 months after your papers are sent. Leaving US without AP will mean your I-485 is cancelled and you will need to resubmit it, if even possible, or wait outside US several months until you get a Green card at the consulate. Leaving US without EAD, will prevent you from working, as you cannot enter on TN anymore, and will need to have the EAD in hand to resume working.
So, your timeline is going to be greatly influenced by how much time you have on your TN. And if your really insist to marry or honeymoon outside US, then I suggest getting civil marriage in US, and then having a ceremonial wedding or honeymoon later, after you have your AP/EAD.
mahzeltov