Luxon or Kurzick

Is there any place in prophecies or nightfall that i can find either of these ambassadors

of course not

Unfortunately, no. The ambassadors can only be found at their respective capital cities (Cavalon/House zu Heltzer) in Factions.

could i use and all campaign trial and then try and make it be4 the time expires or is that possible?

AFAIK you can do it on trial time, but you only have 10 hours so don't waste it. If you have a lvl 20 character ready and don't waste time with side quests it would be possible. You will need to make it to House zu Heltzer for Kurzicks or Cavalon for Luxons.

Since I'm assuming you want to be able to align your guild with kurzicks or luxons, another option is to temporarily give guild leader status to someone you trust who is in factions, then have them do it and give control back.

I guess it would be possible to get a character up to that point of the game within the time you have with a trial version, although I don't know if any allegiences you decide to make would hold after the trial expires. If you're really serious about declaring allegiences like that I would suggest investing in the full version of Factions so that you can get involved in it more fully and enjoy the benefits without having to worry about a timer.

the trials arnt designed to let you get that far.

With a 10 hour trial, you could do it. It's only 6 missions (generally short), plus a few primary quests. The only real problem would be making sure you donn't fail any missions.

I'm going to go ahead and try the free trial and see what happens and if it doesn't work imma get a friend to do it from Factions and transfer