The first perek of Rosh Hashonah talks about Shofar.

דף ב

The Gemorah brings a lot of Halochos to prove when the new year for kings start

Daf Gimmel

Do we count the years of Koresh's reign starting in Nissan?

Daf Daled

The Gemorah proves that Daryoveish used to be a good king but then he stopped being a good king

Daf Hai

If you delay bringing the korban, the animal is still VALID

Daf Vav

There is a maximum amount of how much you may delay your Korban.

Rava says any further day delayed is the Aveiro of Bal T'acher.

Daf Zayin

Is Tishrei the new year for rental homes?

Daf Ches

Both opinions for when the Rosh Hashonah for Maser b'hamoh learn their opinion are from the same Posuk

Daf Tes

If you do not do the other mitzvos of Yovel does the Mitzvah of allowing the land to rest still apply?

Daf Yud

The 3 years of Orlah can either end on Rosh Hashonah or Tu B'Shvat.