Hello,
welcome to the TLPD hunting club
Apart from npcscan (on the curse website, it explains how to delete the cache), you can also download silverdragon, which does the same but has additional tracking methods (nameplate etc).
Then, I'm probably not the first one to direct you to Ponderance and his wealth of information on the website. Read through it, and you'll feel like an expert
http://tlpdresource.com/
Then, during the boring wait, you can rummage through the forums;
http://board.tlpdresource.com/viewforum.php?f=3
And also, a lot of folks here have journals where they document their camp.
Finally, there is no best time to start camping time-lost. The spawntime in Northrend is different from Cataclysm, and he's not a world rare, so the 72hr doesn't apply.
Here is more info on that:
It can in fact spawn in the place of Vyragosa at any time Vyragosa can spawn, even if it's the same day. It has been observed to spawn 9 hours apart. Not the week+ between I previously though and have seen reported. However, it can also be weeks between spawns. Thus I assume, it being random, it could actually spawn two spawns in a row. And on the other side, could spawn months inbetween in extreme cases. I mean, ask people who have ran old strat 600+ times to get rivendare's deathcharger where others get it first drop just happening to be in there. a 'chance' can be a bitch.
After Time-Lost or Vyragosa is killed, it USED TO BE the MINIMUM time before next spawn was 6 hours, with no clear maximum. We had seen 30+ various times. Now, post-shattering, the lowest proven time was at/under an hour. (based on a verified activity stream showing a looted time-forwarded talisman and a helm from vyraone hour apart. The claimed distance was 45 minutes between.) However, the lowest I have seen between so far personally is 4 hours.
http://tlpdresource.com/newfacts.html
Good luck!!
