Been short on time. I had an opportunity to answer a question about what got me interested in the Catholic Church which caused me to write a VERY concise conversion summary.

Here is what got me interested ... the whirlwind short version.

I attended a Billy Graham evangelical church. I got irritated that they wanted to "save Catholics" because "Catholics teach that their sins can be forgiven through indulgences". I knew this was wrong. That was seed #1. I left and I became Episcopalian after getting married. My wife and I discovered that all Christian churches agreed with the Catholic Church in 1930 on contraception. That was seed #2. I read the 39 Articles in the Book of Common prayer and got bent out of shape, mostly about not seeing marriage as a sacrament amongst other beliefs that seemed more akin to the church I used to attend. Seed #3. Then, upon prodding, I discovered that everyone I went to church with differed WILDLY on beliefs and the Episcopal church had few stances on doctrine. Seed #4. Then the reading started. I figured that I had to let Catholics defend their faith rather than taking someone elses word for it.
I read "Rome Sweet Home"
I read "Fundamentalism vs. Catholicism"
I read "Born Fundamentalist, Born Again Catholic"
I watched two tapes of a show that aired on EWTN called "Household of Faith" that detailed common objections to the Church. I realized I agreed with most of it already. I got really excited at the possiblity that the Church founded by Christ on Peter really existed.
I defended infant baptism against the Funadmentalist position using Martin Luther as a source. Seed #5 was found in my reading.
I started reading Dave Armstrong's website. I found his essay on the ECF's and Catholic Distinctive doctrines. Seed #6. At this point I picked up Jurgens' "Faith of the Early Fathers" from my parents. I was stunned. This was the sinker. The early church was Catholic. I read the intro to Newmans Essay on the Development of Doctrine.
Everything else I struggled with was elementary in the sense that I felt at that point to be honest in my relationship with Christ required assent to the Catholic Church.

So

Seed #1: Protestants very frequently misrepresent the Church
Seed #2: History of Christian teaching on contraception
Seed #3: Downplaying of sacramentality of marriage
Seed #4: Diversity of belief on "essentials" within Protestantism was disturbing.
Seed #5: The Catholic Biblical case is solid.
Seed #6: The Catholic historical case is undeniable.

That about sums it up.