Peter Ford is an old pen buddy and one of the best penmen around. After closing Melbourne Pens, this is his new venture: AusPens.com
InkPen is Joel Hamilton's fine site, a great source for vintage Parkers and modern Pelikans.
Nibmeister John Mottishaw's site may be found at nibs.com.
Nib guru Richard Binder keeps his site chock-full of informative articles and essays, glossaries, timelines, and pens for sale.
Gary Kaplan is a fine gentleman and a knowledgeable collector whose site always has varied and interesting pens.
An array of spectacular pens for sale, and a healthy dose of solid and useful pen info is always on hand at David Nishimura's vintagepens.com.
Pen Hero is a great source for all the pen-related links you can handle.
PENguin friend and pen-maker extraordinare Bruno Corsini now boasts a web presence!
Greg Minuskin offers retipping services and a variety of excellent vintage pens, often with special retipped nibs.