add mailing list info

scribblings/more-help.scrbl

@@ -0,0 +1,7 @@
+#lang scribble/manual
+
+@title{Getting more help}
+
+Bugs and feature requests can be submitted as @link["https://github.com/mbutterick/pollen/issues"]{GitHub issues}.
+
+For general tips and how-to questions, use the @link["https://groups.google.com/forum/#!forum/pollenpub"]{Pollen discussion group} at @link["mailto:pollenpub@googlegroups.com"]{pollenpub@"@"googlegroups.com}. I'll also use that list to post major changes and new features.

scribblings/pollen.scrbl

@@ -63,6 +63,8 @@ Or, if you can find a better digital-publishing tool, use that. But I'm never go
 
 @include-section["module-reference.scrbl"]
 
+@include-section["more-help.scrbl"]
+
 @include-section["acknowledgments.scrbl"]
 
 @include-section["license.scrbl"]