At the end of the book of Shemot, we learned how to build the Mishkan, what clothing to sew for the Kohanim, how to create the vessels needed in the Tabernacle. After all the instruction, all the wise-hearted of the nation followed Hashem's instructions, and Moshe actually put all the pieces together to create a place worthy within which Hashem's Schechina could rest.
Hashem tells Moshe to explain the laws of sacrifices to the Jewish people, "When a man among you brings an offering to Hashem: from animals..." (Vayikra: 1:2)
Here G-d calls man, an "Adam", just like Adam, the first human being. The Artscroll Chumash quotes Rashi, who tell us that this is to "imply that just as Adam did not bring stolen animals as offerings, since the whole world was his, so too no one may serve G-d with anything acquired dishonestly."
I read, I think in Rav Tzvi Leshem's sefer, Remptions, that there was a disagreement between the Rambam and the Ramban on the reason for the korbanot. (I hope I didn't make a mistake about this - I'll check, or you check. :) )
I think Rambam felt that Hashem gave the Jewish people the korbanot as a way to wean them away from idol worship and sacrifices to false gods. But the Ramban disagreed. He felt that Hashem truly "enjoyed" the sacrifices of the Jewish people. And he cited Adam, who lived in a world without idol worship, without bad influences, without ulterior motives, and he brought a sacrifice to Hashem.
Yes, Adam had the entire world to himself. He can command over all the animals. He had a direct connection to Hashem, his Father in Heaven. And he brought a korban, inspired by pure love, devotion and gratitude to Hashem.
We read in different places in Tanach where Hashem is angry at the Jewish people, and chastises them. "I don't want your empty sacrifices. I want your obedience."
For Hashem, the purpose of the sacrifices in the Tabernacle and later in the Holy Temple is not so that a sheep or goat or bull can be slaughtered. It is that the Jewish people should follow Hashem's ways and truly become closer to Him. Korban has the same root as the word karov or lekarev, come closer. Hashem wants us to come closer to Him, and He wants us to bring korbanot with pure intentions, just like Adam.
Today, as of this writing, we still do not have the Temple, and the korbanot have not been restored. Instead we have our prayers to temporarily take the place of the korbanot. Just as G-d wants us to bring the sacrifices with a pure heart and pure intentions, so He wants us to lekarev (come closer) to Him in our prayer as well.
When you pick up your siddur (prayer book), approach G-d with a pure heart. Don't just shzzsh shzzhsh through your tefillah. Pray with your heart, and Hashem will listen.