Here's a summary of how it's handled most of the time:
As you stated, most tournaments are those 1.000.000 GS or 1.100.000 GS ones (seen some 1.050.000 GS, too). You spend the money to buy your players, Rerolls and choaching staff (apo, cheerleader, assistant coaches) and Fan Factor (no skills). Most events use the Living Rulebook 5.0 or 4.0 as ruleset. Starplayers/Inducements are banned mostly, although the Halfling Master Chef is allowed as permanent team member in a great number of tourneys.
As for the skills, there are lots of variations. Some allow to give 1 skill after/before every game, or a couple of skills even before the tourney starts. I've seen tournaments giving you stat increases (ST, AG) instead of taking some skills. It's not allowed to give more than 1 skill to 1 player most of the time (again, there are exceptions). In the end, it's really up to the tournament organisators.
Magic healing. Normally, every injury and/or death is healed
after the game. You'll start with the full squad for the next game. You don't gain any regular skills between the games, there's no need to note your players SSP's (although some people still do this for the sake of just knowing). Same thing with winnings or Fan Factor, you don't get any money and the FF won't go up or down.
You'll play a fixed number of games (5 or 6 for those 2 day tourneys). First round is a random draw, subsequent rounds are calculated using the so-called Swiss System. You'll play against an opponent with equal strength (normally your neighbour in the standings), it is taken care that you won't face the same opponent twice. You'll have to report the result of every game (TD's) and how many VSA's you and your opponent made. This is important to resolve ties in the standings and for those extra prices like most TD's award.
Regarding different rosters: You'll learn great many things by looking into
this thread. As a rule of thumb, you'll start with less Rerolls and more positionals than in league play. It's all about getting as many skills as possible. That's why you won't see many Chaos/Nurgle/Khemri teams, chances of winning are pretty low with one of these. That's even more true for those 'fun' teams like Goblins/Halflings/Ogres/Vampires. Although there always are some brave souls trying one of these (don't think they've ever won a regular tourney).