There is no better way to gain an education in pen collecting than to attend a show. Pen shows began as purely vintage events, and while new pen promotion and sales now take up a large part of the action (and on the "public" day or days, virtually all), the majority of weekend participants are there for old pens.
NOTE: Many pen stores periodically host "Pen Fairs". Although there may be some collector participation in such events, they fall far short of even the smallest independently-organized pen show in terms of buying and trading opportunities and variety of offerings.
While most pen shows are publicized as open to the public for but one day Sunday they are in fact open to the public for their full run. The choice is between paying around $5 to get in on Sunday, or paying around $60 for weekend registration (there's usually a discount for booking ahead).
Although more advanced collectors will want to get to a pen show as early as possible and for as long as possible, newcomers are usually quite thoroughly overwhelmed by Sunday's offerings alone. If you do decide to visit a pen show on Sunday, however, it is imperative that you show up earlier rather than later. Many exhibitors will have to be at work the next morning, and will begin packing up well before the show officially closes.
It is also a good idea to equip yourself with paper, ink, and tissue paper if you want to see how prospective purchases write. Many sellers will not be so equipped. Ask before you dip, and refrain from actually filling any pens residual ink can make quite a mess for exhibitors flying home. If you blot the nibs dry after trying them, it will be sincerely appreciated.
Bring along plenty of cash, as many participants sell pens in order to buy more, and will want money they can spend right away. Many vintage exhibitors are amateurs, and some may be from other countries, so credit cards cannot be counted upon. Personal checks will often be accepted, but cash, always!
Pen show auctions generally require payment in cash or traveller's checks, so be prepared if you intend to bid. Show auctions are normally held on Saturday, and are often open at no charge even to those who have not paid for weekend registration. It is imperative that you inspect any item you intend to bid on, since catalog descriptions are often untrustworthy. When you are bidding, don't be slow to raise your paddle dragging out the auction does no one any favors, and may lose you the lot. For some reason, inexperienced bidders seem to like to wait until the auctioneer is about to drop the hammer. This isn't clever or dramatic -- it's just annoying.
Newcomers are often confused about the "Hospitality Suite". This is not a place to sit back and relax amid snacks and refreshments, but rather the trading room provided for participants prior to the opening of the main trading areas on Sunday (and sometimes, Saturday). Setup there is informal, and all may participate, regardless of whether a table has been reserved for Sunday.