I met up with groups of 4-5 guys twice to see the opening rounds of the NCAA basketball tournament - once in Seattle, once in Tucson.
There are four games on the first day (either Thursday or Friday) and then you see the winners square off in two games, two days later. I've enjoyed having the day in between games, since four games that first day is a lot of basketball and it's not like the seats are all that comfortable.
In Tucson, we played 18 holes of golf and had dinner at a tasty Mexican restaurant. Since U of A was on spring break, the most energy was coming from the sports bars showing all the March Madness action. In Seattle, I spent the extra time visiting friends and family.
If you want to see all the games from the opening rounds at the cheapest price, you'll need to have your name drawn in one of the ticket lotteries that takes place about a year in advance (unless you have a way of getting tickets through one of the teams playing).
Fans of losing teams from day 1 often unload tickets, so if you're satisfied with going to fewer games you can buy tickets directly from someone outside the stadium after the game.