The following code produces a title page with the title, authors, and abstract, but the addresses appear at the end of the article. Every variation I can think of produces the same problem. Putting \usepackage{amsaddr}
puts the addresses on the title page, but deletes the author names! (edit: amsaddr needs to be loaded before the author information to avoid the aforementioned error; see answer to question)
I don't know what to do, short of hacking together the title manually, as in the answer to Authors in amsart.
\documentclass[titlepage]{amsart}
\title{The title}%
\author{Author 1}
\author{Author 2}
\address{Addresses of Author 1 and 2}
\email{emails of Authors 1 and 2}
\author{Author 3}
\author{Author 4}
\address{Addresses of Author 3 and 4}
\email{emails of Authors 3 and 4}
\usepackage{lipsum}
\begin{document}
\begin{abstract}
An abstract
\end{abstract}
\maketitle
\lipsum[1]
\end{document}
The appears on the title page
This appears on the next page