I just found a bunch of Shinran's writings translated into English and put online... for you.

Shinran was the most important early figure in Japanese Pure Land Buddhism, which holds that Amitabha so loved the world that he pledged not to enter Nirvana until every other sentient being was chillin' in his special Pure Land, all set to become buddhas themselves just as soon as Gilmore Girls finished.

For beginners, I recommend A Record in Lament of Divergences (歎異抄, Tanni-Shou), which was written not by Shinran himself but by one of his disciples, who wanted to set the record straight about what Shinran actually said. This makes it simple, short and to the point. Chapter 1 goes like this:

弥陀の誓願不思議にたすけられまいらせて、往生をばとぐるなりと信じて、念仏まうさんとおもひたつたこゝろのをこるとき、すなはち摂取不捨の利益にあづけしめたまふなり。
弥陀の本願には老少善悪のひとをえらばれず、ただ信心を要とすしるべし。そのゆへは、罪悪深重、煩悩熾盛の衆生をたすけんがための願にてまします。
しかれば、本願を信ぜんには、他の善も要にあらず、念仏にまさるべき善なきゆへに。悪をもおそるべからず、弥陀の本願をさまたぐるほどの悪なきがゆへにと云々。

When you begin to believe that the Mysteries of Amitabha's Vow will save you and see you reborn [in the Pure Land], and your heart is set upon chanting the Nembutsu, you will immediately receive His blessings, which reach all people and exclude no-one.
Amitabha's Fundamental Vow does not distinguish between the old and the young, nor the good and the evil. Only belief is needed, because the vow was to save all living things, buried deep in sin and evil and burning with worldly desire though we be.
Therefore, if you believe in the Fundamental Vow, no other goodness is required, for there is no goodness greater than the chanting of the Nembutsu. Nor need you fear any evil, for there is no evil which can overcome Amitabha's Fundamental Vow. -- This is what Shinran said.

Hmm... charismatic founder who wanted to save all humanity... no matter what you actually do, faith can get you into heaven... hey, remind you of any other religions?

That was my translation, by the way, the one on the site is different. They're the experts, I'm objective. Compare and contrast!